linuxkpi: Add video/mipi_display.h

Needed by drm-kmod.

Reviewed by: bz
Obtained from: OpenBSD
Sponsored by: Beckhoff Automation GmbH & Co. KG
Differential Revision: https://reviews.freebsd.org/D36103

(cherry picked from commit 73e342328b538e5936f248c03a299884dbe22047)