neon: avoid warnings when "__ARM_NEON_FP" is not defined.

WebKit project recently imported simde 0.8.2
Since then the build for Aarch64 targeting RPi4 boards has started
giving lot of warnings related to the simde header:

  warning: "__ARM_NEON_FP" is not defined, evaluates to 0 [-Wundef]

Add a check to ensure that __ARM_NEON_FP is defined.

Related: https://bugs.webkit.org/show_bug.cgi?id=273789

arm/neon/maxnm.h

@@ -39,7 +39,7 @@ SIMDE_BEGIN_DECLS_
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float16_t
 simde_vmaxnmh_f16(simde_float16_t a, simde_float16_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
     return vmaxnmh_f16(a, b);
   #else
     #if defined(simde_math_fmaxf)
@@ -69,7 +69,7 @@ simde_vmaxnmh_f16(simde_float16_t a, simde_float16_t b) {
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float16x4_t
 simde_vmaxnm_f16(simde_float16x4_t a, simde_float16x4_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
     return vmaxnm_f16(a, b);
   #else
     simde_float16x4_private
@@ -93,7 +93,7 @@ simde_vmaxnm_f16(simde_float16x4_t a, simde_float16x4_t b) {
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float16x8_t
 simde_vmaxnmq_f16(simde_float16x8_t a, simde_float16x8_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
     return vmaxnmq_f16(a, b);
   #else
     simde_float16x8_private
@@ -117,7 +117,7 @@ simde_vmaxnmq_f16(simde_float16x8_t a, simde_float16x8_t b) {
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float32x2_t
 simde_vmaxnm_f32(simde_float32x2_t a, simde_float32x2_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6)
     return vmaxnm_f32(a, b);
   #else
     simde_float32x2_private
@@ -189,7 +189,7 @@ simde_vmaxnm_f64(simde_float64x1_t a, simde_float64x1_t b) {
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float32x4_t
 simde_vmaxnmq_f32(simde_float32x4_t a, simde_float32x4_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6)
     return vmaxnmq_f32(a, b);
   #elif defined(SIMDE_POWER_ALTIVEC_P6_NATIVE)
     return vec_max(a, b);

arm/neon/minnm.h

@@ -39,7 +39,7 @@ SIMDE_BEGIN_DECLS_
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float16_t
 simde_vminnmh_f16(simde_float16_t a, simde_float16_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
     return vminnmh_f16(a, b);
   #else
     #if defined(simde_math_fminf)
@@ -69,7 +69,7 @@ simde_vminnmh_f16(simde_float16_t a, simde_float16_t b) {
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float16x4_t
 simde_vminnm_f16(simde_float16x4_t a, simde_float16x4_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
     return vminnm_f16(a, b);
   #else
     simde_float16x4_private
@@ -93,7 +93,7 @@ simde_vminnm_f16(simde_float16x4_t a, simde_float16x4_t b) {
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float32x2_t
 simde_vminnm_f32(simde_float32x2_t a, simde_float32x2_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6)
     return vminnm_f32(a, b);
   #else
     simde_float32x2_private
@@ -165,7 +165,7 @@ simde_vminnm_f64(simde_float64x1_t a, simde_float64x1_t b) {
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float16x8_t
 simde_vminnmq_f16(simde_float16x8_t a, simde_float16x8_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6) && defined(SIMDE_ARM_NEON_FP16)
     return vminnmq_f16(a, b);
   #else
     simde_float16x8_private
@@ -189,7 +189,7 @@ simde_vminnmq_f16(simde_float16x8_t a, simde_float16x8_t b) {
 SIMDE_FUNCTION_ATTRIBUTES
 simde_float32x4_t
 simde_vminnmq_f32(simde_float32x4_t a, simde_float32x4_t b) {
-  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && (__ARM_NEON_FP >= 6)
+  #if defined(SIMDE_ARM_NEON_A32V8_NATIVE) && defined(__ARM_NEON_FP) && (__ARM_NEON_FP >= 6)
     return vminnmq_f32(a, b);
   #elif SIMDE_NATURAL_VECTOR_SIZE_GE(128) && defined(SIMDE_FAST_NANS)
     return simde_vbslq_f32(simde_vcleq_f32(a, b), a, b);

simde-features.h

@@ -349,7 +349,7 @@
 #endif
 
 #if !defined(SIMDE_ARM_NEON_A32V8_NATIVE) && !defined(SIMDE_ARM_NEON_A32V8_NO_NATIVE) && !defined(SIMDE_NO_NATIVE)
-  #if defined(SIMDE_ARCH_ARM_NEON) && SIMDE_ARCH_ARM_CHECK(8,0) && (__ARM_NEON_FP & 0x02)
+  #if defined(SIMDE_ARCH_ARM_NEON) && SIMDE_ARCH_ARM_CHECK(8,0) && defined (__ARM_NEON_FP) && (__ARM_NEON_FP & 0x02)
     #define SIMDE_ARM_NEON_A32V8_NATIVE
   #endif
 #endif