Modify ARM .S code so it can be processed by both gnu-as and llvm-mc.

src/trusted/service_runtime/nacl.scons

Index: src/trusted/service_runtime/nacl.scons
===================================================================
--- src/trusted/service_runtime/nacl.scons	(revision 7372)
+++ src/trusted/service_runtime/nacl.scons	(working copy)
@@ -44,8 +44,10 @@
   if asm_env.Bit('bitcode'):
     asm_env.PNaClForceNative()
     # NOTE: "PNACL_AS" controls small code adaptions needed for  the
-    # pnacl assembler
-    asm_env.Append(ASFLAGS='-DPNACL_AS=1')
+    # pnacl assembler but we do not use the pnacl assembler for ARM yet
+    # BUG: http://code.google.com/p/nativeclient/issues/detail?id=1968
+    if not env.Bit('target_arm'):
+      asm_env.Append(ASFLAGS='-DPNACL_AS=1')
     # Windows uses CC for assembling
     asm_env.Append(CFLAGS='-DPNACL_AS=1')
   link_cmd = ('${LD} -e _start ${TEXT_START} ${RO_START} ${RW_START}' +