MAINTAINERS: ACPI / video: update a file name in drivers/acpi/

We renamed drivers/acpi/video.c to drivers/acpi/acpi_video.c in commit
14ca7a47 ('acpi-video-detect: video: Make video_detect code part of
the video module').

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>