MT#55283 restrict ifunc usage to glibc

probably fixes #1751

Change-Id: Id78d91ef74d60be58e537db85c54bc9447406e34

lib/codeclib.c

@@ -4415,7 +4415,7 @@ static const char evs_amr_io_compact_cmr[8] = {
 };
 
 
-#if defined(__x86_64__) && !defined(ASAN_BUILD) && HAS_ATTR(ifunc)
+#if defined(__x86_64__) && !defined(ASAN_BUILD) && HAS_ATTR(ifunc) && defined(__GLIBC__)
 static void mvr2s_dynlib_wrapper(float *in, const uint16_t len, int16_t *out) {
 	evs_syn_output(in, len, out);
 }

lib/mix_buffer.c

@@ -53,7 +53,7 @@ static void s16_mix_in_c(void *restrict dst, const void *restrict src, unsigned
 }
 
 
-#if defined(__x86_64__) && !defined(ASAN_BUILD) && HAS_ATTR(ifunc)
+#if defined(__x86_64__) && !defined(ASAN_BUILD) && HAS_ATTR(ifunc) && defined(__GLIBC__)
 static mix_in_fn_t *resolve_s16_mix_in(void) {
 	if (rtpe_has_cpu_flag(RTPE_CPU_FLAG_AVX512BW))
 		return s16_mix_in_avx512;