src/lib: Move asmlinkage before type

Fix the following warning detected by checkpatch.pl:

WARNING: storage class should be at the beginning of the declaration

TEST=Build and run on Galileo Gen2

Change-Id: I7d3135466634a4bb84dcef16dbd68754f8d8d6c2
Signed-off-by: Lee Leahy <Leroy.P.Leahy@intel.com>
Reviewed-on: https://review.coreboot.org/18760
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/lib/gcc.c

@@ -25,7 +25,7 @@
  * specific implementations may vary
  */
 #define WRAP_LIBGCC_CALL(type, name) \
-	type __real_##name(type a, type b) asmlinkage; \
+	asmlinkage type __real_##name(type a, type b); \
 	type __wrap_##name(type a, type b); \
 	type __wrap_##name(type a, type b) { return __real_##name(a, b); }