[MIPS] Add MIPS support

Signed-off-by: Chris Dearman <chris@mips.com>
diff --git a/make/asr/Makefile.config b/make/asr/Makefile.config
index 368fa5c..4f951aa 100644
--- a/make/asr/Makefile.config
+++ b/make/asr/Makefile.config
@@ -14,19 +14,22 @@
 ifeq ($(TARGET_ARCH),arm)
   ASR_CPU         = ARM
   ASR_TARGET_CPU  = ARM
-else
+endif
 ifeq ($(TARGET_ARCH),x86)
   ASR_CPU         = I86
   ASR_TARGET_CPU  = I86
-else
+endif
 ifeq ($(TARGET_ARCH),sh)
   ASR_CPU         = SH4
   ASR_TARGET_CPU  = SH4
-else
+endif
+ifeq ($(TARGET_ARCH),mips)
+  ASR_CPU         = MIPS
+  ASR_TARGET_CPU  = MIPS
+endif
+ifeq ($(ASR_TARGET_CPU),)
   $(error Unsupported TARGET_ARCH for ASR)
 endif
-endif
-endif
 
 ASR_COMPILER      = GNU