staging: mt7621-mmc: Fix line size exceeding 80 columns

This patch fixes checkpatch.pl warning and check:
WARNING: line over 80 characters
CHECK: Alignment should match open parenthesis

Signed-off-by: Sankalp Negi <sankalpnegi2310@gmail.com>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>