S390: Add platform specific atomic ops impl

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
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@@ skipping 1520 matching lines @@
         '../../src/base/adapters.h',
         '../../src/base/atomicops.h',
         '../../src/base/atomicops_internals_arm64_gcc.h',
         '../../src/base/atomicops_internals_arm_gcc.h',
         '../../src/base/atomicops_internals_atomicword_compat.h',
         '../../src/base/atomicops_internals_mac.h',
         '../../src/base/atomicops_internals_mips_gcc.h',
         '../../src/base/atomicops_internals_mips64_gcc.h',
         '../../src/base/atomicops_internals_portable.h',
         '../../src/base/atomicops_internals_ppc_gcc.h',
+        '../../src/base/atomicops_internals_s390_gcc.h',
         '../../src/base/atomicops_internals_tsan.h',
         '../../src/base/atomicops_internals_x86_gcc.cc',
         '../../src/base/atomicops_internals_x86_gcc.h',
         '../../src/base/atomicops_internals_x86_msvc.h',
         '../../src/base/bits.cc',
         '../../src/base/bits.h',
         '../../src/base/build_config.h',
         '../../src/base/compiler-specific.h',
         '../../src/base/cpu.cc',
         '../../src/base/cpu.h',
@@ skipping 576 matching lines @@
         }],
         ['want_separate_host_toolset==1', {
           'toolsets': ['host'],
         }, {
           'toolsets': ['target'],
         }],
       ],
     },
   ],
 }