ARM: clean up code now that ARMv6 is the baseline.

src/arm/cpu-arm.cc

 // Copyright 2006-2009 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 90 matching lines @@
     "2:                  \n\t"
         : "=r" (beg)
         : "0" (beg), "r" (end), "r" (flg), "r" (__ARM_NR_cacheflush)
         : "r3");
   #endif
 #endif
 }
 
 
 void CPU::DebugBreak() {
-#if !defined (__arm__) || !defined(CAN_USE_ARMV5_INSTRUCTIONS)
+#if !defined (__arm__)
   UNIMPLEMENTED();  // when building ARM emulator target
 #else
   asm volatile("bkpt 0");
 #endif
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM