tegra: add hdmionly compat option
 * ifdef double buffering fixes
 * lock to 1280/xxxx resolution (every device should be compatible with this)
Add support for kexec-hardboot
"Allows hard booting (i.e., with a full hardware reboot) to a kernel
previously loaded in memory by kexec.  This works around the problem of
soft-booted kernel hangs due to improper device shutdown and/or
reinitialization."
More info in /arch/arm/Kconfig.

Original author: Mike Kasick <mike@kasick.org>
These patches are ported from Asus TF201, to which it
was ported by Jens Andersen <jens.andersen@gmail.com>.