btrfs: use printk_get_level and printk_skip_level, add __printf, fix fallout
Use the generic printk_get_level() to search a message for a kern_level.
Add __printf to verify format and arguments. Fix a few messages that
had mismatches in format and arguments. Add #ifdef CONFIG_PRINTK blocks
to shrink the object size a bit when not using printk.
[akpm@linux-foundation.org: whitespace tweak] Signed-off-by: Joe Perches <joe@perches.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Chris Mason <chris.mason@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>