Bug 1663898: Really enable Cranelift by default on aarch64 builds; r=froydnj

Differential Revision: https://phabricator.services.mozilla.com/D89600

modules/libpref/init/all.js

@@ -1095,7 +1095,7 @@ pref("javascript.options.wasm_baselinejit",       true);
 // compilation, and Ion is not available.
 // On every other tier-1 platform, Ion is the default, and Cranelift is
 // disabled.
-#ifdef _ARM64_
+#ifdef MOZ_AARCH64
   #ifdef ENABLE_WASM_CRANELIFT
     pref("javascript.options.wasm_cranelift",     true);
   #endif

modules/libpref/moz.build

@@ -151,6 +151,9 @@ if CONFIG['MOZ_SERVICES_SYNC']:
 if CONFIG['MOZ_BUILD_APP'] == 'browser':
     DEFINES['MOZ_BUILD_APP_IS_BROWSER'] = True
 
+if CONFIG['CPU_ARCH'] == 'aarch64':
+    DEFINES['MOZ_AARCH64'] = True
+
 if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'android':
     if not CONFIG['MOZ_ANDROID_FAT_AAR_ARCHITECTURES']:
         FINAL_TARGET_PP_FILES[CONFIG['ANDROID_CPU_ARCH']] += [