Remove unused local variables as reported by gcc's -Wunused-but-set-variable option.

 [ bp: simplify commit message. ]
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: https://lkml.kernel.org/r/20181211095207.25936-1-yuehaibing@huawei.com