MIPS: allow asm/cpu.h to be included from assembly

Add guards around the enum to allow including cpu.h from assembly.
Signed-off-by: NJonas Gorski <jogo@openwrt.org>
Signed-off-by: NJohn Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6238/

arch/mips/include/asm/cpu.h

@@ -249,6 +249,8 @@
 
 #define FPIR_IMP_NONE		0x0000
 
+#if !defined(__ASSEMBLY__)
+
 enum cpu_type_enum {
 	CPU_UNKNOWN,
 
@@ -301,6 +303,7 @@ enum cpu_type_enum {
 	CPU_LAST
 };
 
+#endif /* !__ASSEMBLY */
 
 /*
  * ISA Level encodings