lock_super() is unnecessary for setting super-block feature flags.  Use the
provided *_SET_COMPAT_FEATURE() macros as well.
Signed-off-by: NAndreas Gruenbacher <agruen@suse.de>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>