ocfs2: clean up redundant function declarations

ocfs2: clean up redundant function declarations

ocfs2_extend_allocation() has been deleted, clean up its declaration.
Also change the static function name from __ocfs2_extend_allocation() to
ocfs2_extend_allocation() to be consistent with the corresponding trace
events as well as comments for ocfs2_lock_allocators().

Link: http://lkml.kernel.org/r/[email protected]
Fixes: 964f14a0d350 ("ocfs2: clean up some dead code")
Signed-off-by: Jia Guo <[email protected]>
Acked-by: Joseph Qi <[email protected]>
Reviewed-by: Jun Piao <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>