fix merp arm64 (#47331)

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Co-authored-by: vargaz <vargaz@users.noreply.github.com>

Author: monojenkins

src/mono/configure.ac

@@ -408,13 +408,6 @@ case "$host" in
 		host_sunos=yes
 		;;
 	*-*-darwin*)
-		# Temporary workaround for Apple Silicon
-		# config.guess returns arm-apple-darwin20.0.0
-		if test $ac_cv_host = arm-apple-darwin20.0.0 -o $ac_cv_target = arm-apple-darwin20.0.0; then
-		   echo "You are running on Apple Silicon, but using an old config.guess, invoke configure like this:"
-		   echo "Run configure using ./configure --host=aarch64-apple-darwin20.0.0 --target=aarch64-apple-darwin20.0.0"
-		   exit 1
-		fi
 		parallel_mark="Disabled_Currently_Hangs_On_MacOSX"
 		host_darwin=yes
 		target_mach=yes

src/mono/mono/utils/mono-merp.c

@@ -129,7 +129,8 @@ typedef enum {
 	MerpArchx86_64 = 1,
 	MerpArchx86 = 2,
 	MerpArchPPC = 3,
-	MerpArchPPC64 = 4
+	MerpArchPPC64 = 4,
+	MerpArchARM64 = 5
 } MerpArch;
 
 typedef enum
@@ -218,6 +219,8 @@ get_merp_bitness (MerpArch arch)
 			return "x64";
 		case MerpArchx86:
 			return "x32";
+		case MerpArchARM64:
+			return "arm64";
 		default:
 			g_assert_not_reached ();
 	}
@@ -234,6 +237,8 @@ get_merp_arch (void)
 	return MerpArchPPC;
 #elif defined(TARGET_POWERPC64)
 	return MerpArchPPC64;
+#elif defined(TARGET_ARM64)
+	return MerpArchARM64;
 #else
 	g_assert_not_reached ();
 #endif