ARM: Rename the "new_eip" field in NaClThreadContext to "new_prog_ctr"

src/trusted/service_runtime/arch/x86_32/nacl_switch_32.S

 /*
  * Copyright (c) 2012 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /*
  * NaCl Secure Runtime
  */
 
@@ skipping 74 matching lines @@
 /*
  * For DO_USING_ARG_IN_ECX get the thread context from ecx instead of the
  * stack.
  */
 .if MACROARG2 != DO_USING_ARG_IN_ECX
         /* do not leak info to app */
         xorl    %ecx, %ecx
         /* xorl will leave eflags in a known state, so no info leaks */
         popl    %ecx
 .endif
-        movl    0x30(%ecx), %edx /* new_eip */
+        movl    0x30(%ecx), %edx /* new_prog_ctr */
         movl    0x14(%ecx), %ebp /* frame_ptr.ptr_32.ptr */
         movl    0x8(%ecx), %edi /* edi */
         movl    0x4(%ecx), %esi /* esi */
         movl    0(%ecx), %ebx /* ebx */
 
         movw    0x2e(%ecx), %gs /* gs */
         movw    0x2c(%ecx), %fs /* fs */
         movw    0x2a(%ecx), %es /* es */
 
         /*
          * Clear the x87 state.  Then restore the untrusted code's control word.
          */
         fninit
         fldcw   0x22(%ecx)
 
         ljmp    *0x38(%ecx) /* springboard address */
 ENDMACRO
 
         switcher NaClSwitchNoSSE, DO_NONE
         switcher NaClSwitchSSE, DO_SSE
         switcher NaClSwitchAVX, DO_AVX
 
 /* Generate register only version on OSX. */
 #if NACL_OSX
         switcher NaClSwitchNoSSEViaECX, DO_USING_ARG_IN_ECX
 #endif