Adds support for ARMv6.

tools/gyp/configurations_make.gypi

 # Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 {
   'variables': {
     'dart_debug_optimization_level%': '2',
   },
   'target_defaults': {
     'configurations': {
@@ skipping 37 matching lines @@
           'ARM_FLOAT_ABI_HARD',
         ],
       },
 
       'Dart_Linux_arm_Base': {
         'abstract': 1,
         'target_conditions': [
         ['_toolset=="target"', {
           'cflags': [
             '-marm',
-            '-march=armv7-a',
             '-mfpu=vfp',
             '-Wno-psabi', # suppresses va_list warning
             '-fno-strict-overflow',
           ],
           'defines': [
             # In build.py, we specify the hf compiler.
             'ARM_FLOAT_ABI_HARD',
           ],
         }],
         ['_toolset=="host"', {
@@ skipping 43 matching lines @@
           # The sampling profiler uses the frame pointer to walk the stack.
           '-fno-omit-frame-pointer',
           # Clang on Linux will still omit frame pointers from leaf functions
           # unless told otherwise:
           # '-mno-omit-leaf-frame-pointer',
         ],
       },
     },
   },
 }