MIPS: Squash lines for simple wrapper functions

Remove unneeded variables and assignments.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14260/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>