Use _Float16 in C++ on aarch64 with GCC 13+

It seems GCC supports _Float16 in C++ on aarch64 since GCC 13, at least
according to my quick tests on godbolt.org.

(It was already supported in C since GCC 7.)

simde-f16.h

@@ -76,6 +76,7 @@ SIMDE_BEGIN_DECLS_
       defined(SIMDE_X86_AVX512FP16_NATIVE) || \
       (defined(SIMDE_ARCH_X86_SSE2) && HEDLEY_GCC_VERSION_CHECK(12,0,0)) || \
       (defined(SIMDE_ARCH_AARCH64) && HEDLEY_GCC_VERSION_CHECK(7,0,0) && !defined(__cplusplus)) || \
+      (defined(SIMDE_ARCH_AARCH64) && HEDLEY_GCC_VERSION_CHECK(13,0,0)) || \
       ((defined(SIMDE_ARCH_X86_SSE2) || defined(SIMDE_ARCH_AMD64)) && SIMDE_DETECT_CLANG_VERSION_CHECK(15,0,0)) || \
       (!(defined(SIMDE_ARCH_X86) || defined(SIMDE_ARCH_AMD64)) && SIMDE_DETECT_CLANG_VERSION_CHECK(6,0,0))) || \
       defined(SIMDE_ARCH_RISCV_ZVFH)