Backport htscodecs improvement: Check for HWCAP_ASIMD

Apply part of PR samtools/htscodecs#91. The manylinux2014_aarch64 image
is based on CentOS 7 and uses glibc 2.17, while these aarch64 capability
bits were added in v2.24. We'll build aarch64 wheels on manylinux_2_28
but might as well ensure manylinux2014 builds too.

htslib/htscodecs/htscodecs/rANS_static4x16pr.c

@@ -1018,15 +1018,15 @@ unsigned char *(*rans_dec_func(int do_simd, int order))
 static inline int have_neon() {
 #if defined(__linux__) && defined(__arm__)
     return (getauxval(AT_HWCAP) & HWCAP_NEON) != 0;
-#elif defined(__linux__) && defined(__aarch64__)
+#elif defined(__linux__) && defined(__aarch64__) && defined(HWCAP_ASIMD)
     return (getauxval(AT_HWCAP) & HWCAP_ASIMD) != 0;
 #elif defined(__APPLE__)
     return 1;
 #elif defined(__FreeBSD__) && defined(__arm__)
     u_long cap;
     if (elf_aux_info(AT_HWCAP, &cap, sizeof cap) != 0) return 0;
     return (cap & HWCAP_NEON) != 0;
-#elif defined(__FreeBSD__) && defined(__aarch64__)
+#elif defined(__FreeBSD__) && defined(__aarch64__) && defined(HWCAP_ASIMD)
     u_long cap;
     if (elf_aux_info(AT_HWCAP, &cap, sizeof cap) != 0) return 0;
     return (cap & HWCAP_ASIMD) != 0;