checkpatch: remove unnecessary + after {8,8}

There's a useless "+" use that needs to be removed as perl 5.20 emits a
"Useless use of greediness modifier '+'" message each time it's hit.

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