Prepare switch from a64 to arm64

tools/gyp/v8.gyp

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 627 matching lines @@
             '../../src/arm/lithium-gap-resolver-arm.cc',
             '../../src/arm/lithium-gap-resolver-arm.h',
             '../../src/arm/macro-assembler-arm.cc',
             '../../src/arm/macro-assembler-arm.h',
             '../../src/arm/regexp-macro-assembler-arm.cc',
             '../../src/arm/regexp-macro-assembler-arm.h',
             '../../src/arm/simulator-arm.cc',
             '../../src/arm/stub-cache-arm.cc',
           ],
         }],
-        ['v8_target_arch=="a64"', {
+        ['v8_target_arch=="a64" or v8_target_arch=="arm64"', {
           'sources': [  ### gcmole(arch:a64) ###
             '../../src/a64/assembler-a64.cc',
             '../../src/a64/assembler-a64.h',
             '../../src/a64/assembler-a64-inl.h',
             '../../src/a64/builtins-a64.cc',
             '../../src/a64/codegen-a64.cc',
             '../../src/a64/codegen-a64.h',
             '../../src/a64/code-stubs-a64.cc',
             '../../src/a64/code-stubs-a64.h',
             '../../src/a64/constants-a64.h',
@@ skipping 507 matching lines @@
         }],
         ['v8_compress_startup_data=="bz2"', {
           'libraries': [
             '-lbz2',
           ]
         }],
       ],
     },
   ],
 }