FAT: Fix printk format strings

This makes sure printk format strings contain no more than a single line.

Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
[the message was tweaked.]
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>