checkpatch: add more exceptions to 80 char lines

Add new logging functions netdev_<level> and netif_<level>.
Don't complain if the only thing on a line is a quoted string.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>