[MIPS] Build compiler-rt for direct-to-nacl

Build compiler-rt for MIPS direct-to-nacl.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=4205
R=dschuff@chromium.org

Review URL: https://codereview.chromium.org/1173603002.
diff --git a/make/platform/clang_nacl.mk b/make/platform/clang_nacl.mk
index e7448d9..b6a8505 100644
--- a/make/platform/clang_nacl.mk
+++ b/make/platform/clang_nacl.mk
@@ -52,8 +52,15 @@
 else
 ifeq ($(call contains,le32,$(CompilerTargetArch)),true)
 # This is really for mips, but mips uses le32 bitcode
+# TODO(petarj): Remove this if possible.
 Configs += full-mips32
 Arch.full-mips32 := mips32
+else
+ifeq ($(call contains,mipsel,$(CompilerTargetArch)),true)
+# This is for mips d2n
+Configs += full-mips32
+Arch.full-mips32 := mips32
+endif
 endif
 endif
 endif