checkpatch: emit an error on formats with 0x%<decimal>

Using 0x%d is wrong.  Emit a message when it happens.

Miscellanea:

Improve the %Lu warning to match formats like %16Lu.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>