[MIPS] Adding binutils changes for MIPS/NaCl architecture.

binutils-2.20/ld/configure.tgt

 # This is the linker target specific file.  This is invoked by the
 # autoconf generated configure script.  Putting it in a separate shell
 # file lets us skip running autoconf when modifying target specific
 # information.
 
 # This file switches on the shell variable ${targ}, and sets the
 # following shell variables:
 #  targ_emul            name of linker emulation to use
 #  targ_extra_emuls     additional linker emulations to provide
 #  targ_extra_libpath   additional linker emulations using LIB_PATH
@@ skipping 387 matching lines @@
                         targ_extra_emuls="elf32ebmipvxworks" ;;
 mips*-*-vxworks*)       targ_emul=elf32ebmipvxworks
                         targ_extra_emuls="elf32elmipvxworks" ;;
 mips*-*-windiss)        targ_emul=elf32mipswindiss ;;
 mips64*el-*-linux-*)    targ_emul=elf32ltsmipn32
                         targ_extra_emuls="elf32btsmipn32 elf32ltsmip elf32btsmip elf64ltsmip elf64btsmip"
                         targ_extra_libpath=$targ_extra_emuls ;;
 mips64*-*-linux-*)      targ_emul=elf32btsmipn32
                         targ_extra_emuls="elf32ltsmipn32 elf32btsmip elf32ltsmip elf64btsmip elf64ltsmip"
                         targ_extra_libpath=$targ_extra_emuls ;;
+mips*el-*-nacl)         targ_emul=elf32ltsmip_nacl ;;
 mips*el-*-linux-*)      targ_emul=elf32ltsmip
                         targ_extra_emuls="elf32btsmip elf32ltsmipn32 elf64ltsmip elf32btsmipn32 elf64btsmip"
                         targ_extra_libpath=$targ_extra_emuls ;;
 mips*-*-linux-*)        targ_emul=elf32btsmip
                         targ_extra_emuls="elf32ltsmip elf32btsmipn32 elf64btsmip elf32ltsmipn32 elf64ltsmip"
                         targ_extra_libpath=$targ_extra_emuls ;;
 mips64*el-*-freebsd-* | mips64*el-*-kfreebsd*-gnu)
                         targ_emul=elf32ltsmipn32_fbsd
                         targ_extra_emuls="elf32ltsmip elf32btsmip elf32ltsmipn32 elf32btsmipn32 elf64ltsmip elf64btsmip elf32ltsmip_fbsd elf32btsmip_fbsd elf32btsmipn32_fbsd elf64ltsmip_fbsd elf64btsmip_fbsd"
                         targ_extra_libpath=$targ_extra_emuls ;;
@@ skipping 313 matching lines @@
   ;;
 
 *-*-netbsd*)
   ;;
 
 alpha*-*-*)
   NATIVE_LIB_DIRS='/usr/local/lib /usr/ccs/lib /lib /usr/lib'
   ;;
 
 esac