fix cpu detect on apple m1 arm64

BUG=aomedia:3147

Change-Id: Id9b40c5120ecd2b6f10da6fa51be64d8dab791fe
(cherry picked from commit a54dda4fd2cb3c38b3e94d4a16fd28ebaa22caaf)

aom_ports/arm_cpudetect.c

diff --git a/aom_ports/arm_cpudetect.c b/aom_ports/arm_cpudetect.c
index 1696f15..23d3aa5 100644
--- a/aom_ports/arm_cpudetect.c
+++ b/aom_ports/arm_cpudetect.c
@@ -38,7 +38,7 @@
   return env && *env ? (int)strtol(env, NULL, 0) : ~0;
 }
 
-#if !CONFIG_RUNTIME_CPU_DETECT
+#if !CONFIG_RUNTIME_CPU_DETECT || defined(__APPLE__)
 
 int aom_arm_cpu_caps(void) {
   /* This function should actually be a no-op. There is no way to adjust any of
@@ -56,7 +56,7 @@
   return flags & mask;
 }
 
-#elif defined(_MSC_VER) /* end !CONFIG_RUNTIME_CPU_DETECT */
+#elif defined(_MSC_VER) /* end !CONFIG_RUNTIME_CPU_DETECT || __APPLE__ */
 /*For GetExceptionCode() and EXCEPTION_ILLEGAL_INSTRUCTION.*/
 #define WIN32_LEAN_AND_MEAN
 #define WIN32_EXTRA_LEAN