mm: codgin-style fixes

Fix whitespace issues, extraneous braces.

Link: http://lkml.kernel.org/r/1485992240-10986-5-git-send-email-me@tobin.cc


Signed-off-by: Tobin C Harding <me@tobin.cc>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>