src/lib: Remove unnecessary code

Fix the following warnings detected by checkpatch.pl:

WARNING: break is not useful after a goto or return
WARNING: Statements terminations use 1 semicolon
WARNING: else is not generally useful after a break or return
WARNING: void function return statements are not generally useful

TEST=Build and run on Galileo Gen2

Change-Id: I6f095c4e9cb1ee4ff2ebdf095ef612e1a8393231
Signed-off-by: Lee Leahy <Leroy.P.Leahy@intel.com>
Reviewed-on: https://review.coreboot.org/18762
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/lib/imd.c

@@ -439,7 +439,7 @@ int imd_create_tiered_empty(struct imd *imd,
 				size_t lg_root_size, size_t lg_entry_align,
 				size_t sm_root_size, size_t sm_entry_align)
 {
-	size_t sm_region_size;;
+	size_t sm_region_size;
 	const struct imd_entry *e;
 	struct imdr *imdr;