[MIPS] Fix missing definitions for MIPS arch in build and driver scripts

pnacl/driver/pnacl-nativeld.py

 #!/usr/bin/python
 # 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.
 #
 #
 # This is a thin wrapper for native LD. This is not meant to be
 # used by the user, but is called from pnacl-translate.
 # This implements the native linking part of translation.
 #
@@ skipping 136 matching lines @@
   ( '(-t)',                       PassThrough),
   ( ('-y','(.*)'),                PassThrough),
   ( ('(-defsym)','(.*)'),         PassThrough),
   ( '-export-dynamic',            PassThrough),
 
   ( '(--print-gc-sections)',      PassThrough),
   ( '(--gc-sections)',            PassThrough),
   ( '(--unresolved-symbols=.*)',  PassThrough),
   ( '(--dynamic-linker=.*)',      PassThrough),
 
-  ( '-melf_nacl',          "env.set('ARCH', 'X8632')"),
-  ( ('-m','elf_nacl'),     "env.set('ARCH', 'X8632')"),
-  ( '-melf64_nacl',        "env.set('ARCH', 'X8664')"),
-  ( ('-m','elf64_nacl'),   "env.set('ARCH', 'X8664')"),
-  ( '-marmelf_nacl',       "env.set('ARCH', 'ARM')"),
-  ( ('-m','armelf_nacl'),  "env.set('ARCH', 'ARM')"),
+  ( '-melf_nacl',            "env.set('ARCH', 'X8632')"),
+  ( ('-m','elf_nacl'),       "env.set('ARCH', 'X8632')"),
+  ( '-melf64_nacl',          "env.set('ARCH', 'X8664')"),
+  ( ('-m','elf64_nacl'),     "env.set('ARCH', 'X8664')"),
+  ( '-marmelf_nacl',         "env.set('ARCH', 'ARM')"),
+  ( ('-m','armelf_nacl'),    "env.set('ARCH', 'ARM')"),
+  ( '-mmipselelf_nacl',      "env.set('ARCH', 'MIPS32')"),
+  ( ('-m','mipselelf_nacl'), "env.set('ARCH', 'MIPS32')"),
 
   # Inputs and options that need to be kept in order
   ( '(--no-as-needed)',    "env.append('INPUTS', $0)"),
   ( '(--as-needed)',       "env.append('INPUTS', $0)"),
   ( '(--start-group)',     "env.append('INPUTS', $0)"),
   ( '(--end-group)',       "env.append('INPUTS', $0)"),
   ( '(-Bstatic)',          "env.append('INPUTS', $0)"),
   ( '(-Bdynamic)',         "env.append('INPUTS', $0)"),
   # This is the file passed from llc during translation (used to be via shmem)
   ( ('--llc-translated-file=(.*)'), "env.append('INPUTS', $0)\n"
@@ skipping 150 matching lines @@
 def LinkerFiles(args):
   ret = []
   for f in args:
     if IsFlag(f):
       continue
     else:
       if not pathtools.exists(f):
         Log.Fatal("Unable to open '%s'", pathtools.touser(f))
       ret.append(f)
   return ret