PNaCl: Add more MIPS support to the toolchain

pnacl/driver/pnacl-ld.py

Index: pnacl/driver/pnacl-ld.py
diff --git a/pnacl/driver/pnacl-ld.py b/pnacl/driver/pnacl-ld.py
index 07f2de72056c69d2e4f5a9c20972a63077f0551e..71ca7ab6539a1f4c3c89c675bf7dbc6c7053cf29 100755
--- a/pnacl/driver/pnacl-ld.py
+++ b/pnacl/driver/pnacl-ld.py
@@ -89,12 +89,14 @@ EXTRA_ENV = {
   'LIBS_ARM'         : '${BASE_GLIBC}/lib-arm',
   'LIBS_X8632'       : '${BASE_GLIBC}/lib-x86-32',
   'LIBS_X8664'       : '${BASE_GLIBC}/lib-x86-64',
+  'LIBS_MIPS32'      : '${BASE_GLIBC}/lib-mips32',
   # HACK-END
 
   'LD_GOLD_OFORMAT'        : '${LD_GOLD_OFORMAT_%ARCH%}',
   'LD_GOLD_OFORMAT_ARM'    : 'elf32-littlearm',
   'LD_GOLD_OFORMAT_X8632'  : 'elf32-nacl',
   'LD_GOLD_OFORMAT_X8664'  : 'elf64-nacl',
+  'LD_GOLD_OFORMAT_MIPS32' : 'elf32-tradlittlemips',
 
   'BCLD'      : '${LD_GOLD}',
   'BCLD_FLAGS': '--native-client --oformat ${LD_GOLD_OFORMAT} -Ttext=0x20000 ' +