Fix vqshlud_n_s64 implementation to be 64-bit.

The scalar vqshlud_n_s64 function was wrong, and there was no test
case for it (or the scalar 32 bit form).  Add test cases for the
scalar functions (test vectors generated on GCE ARMv9 system),
validate the fix for the 64-bit scalar form.

arm/neon/qshlu_n.h

@@ -94,8 +94,8 @@ SIMDE_FUNCTION_ATTRIBUTES
 uint64_t
 simde_vqshlud_n_s64(int64_t a, const int n)
     SIMDE_REQUIRE_CONSTANT_RANGE(n, 0, 63) {
-  uint32_t r = HEDLEY_STATIC_CAST(uint32_t, a << n);
-  r |= (((r >> n) != HEDLEY_STATIC_CAST(uint32_t, a)) ? UINT32_MAX : 0);
+  uint64_t r = HEDLEY_STATIC_CAST(uint64_t, a << n);
+  r |= (((r >> n) != HEDLEY_STATIC_CAST(uint64_t, a)) ? UINT64_MAX : 0);
   return (a < 0) ? 0 : r;
 }
 #if defined(SIMDE_ARM_NEON_A64V8_NATIVE)