We don't have to #if guard prototypes.

This also fixes a bug observed by Randy Dunlap due to a misspelled
option in the #if.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>