Staging: mt7621-pci: Fix alignment warnings

Fix the alignment issue pointed out by checkpatch

Signed-off-by: Siddhant Gupta <siddhantgupta416@gmail.com>
Link: https://lore.kernel.org/r/20201106093021.GA25237@Sleakybeast


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>