ACPI: video: Drop dmi_system_id.ident settings from video_detect_dmi_table[]

The .ident field of the dmi_system_id structs in the
video_detect_dmi_table[] is not used by the code.

Change all .ident = "..." assignments to comments, this reduces the
size of video_detect.o / video.ko by about 1500 bytes.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>