BEFS: logging cleanup

Summary:
 - all printk(KERN_foo converted to pr_foo()
 - add pr_fmt and remove redundant prefixes
 - convert befs_() to va_format (based on patch by Joe Perches)
 - remove non standard %Lu
 - use __func__ for all debugging

[akpm@linux-foundation.org: fix printk warnings, reported by Fengguang]
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Cc: Fengguang Wu <fengguang.wu@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>