Revert "contrib: gcrypt: disable asm for macOS aarch64 for now"

This reverts commit 8edd1a3.

It seems to build properly. Modern should support arm64 properly.

We also build ASM for iOS/tvOS/xrOS since HAVE_BSD is no longer
set for these (4bfdaf5).

contrib/src/gcrypt/rules.mak

@@ -54,9 +54,6 @@ endif
 endif
 ifdef HAVE_MACOSX
 GCRYPT_CONF += --disable-aesni-support
-ifeq ($(ARCH),aarch64)
-GCRYPT_CONF += --disable-asm --disable-arm-crypto-support
-endif
 endif
 ifdef HAVE_BSD
 GCRYPT_CONF += --disable-asm --disable-aesni-support