video: tegra: add host1x support to driver

video: tegra: add host1x support to driver

includes changes by:

Antti Hatala <ahatala@nvidia.com> (1)
Gary King <gking@nvidia.com> (1)
Erik Gilling <konkers@android.com> (2)

Antti Hatala <ahatala@nvidia.com>
video: tegra: dc: use nvhost driver for host1x power management

Gary King <gking@nvidia.com>
video: tegra: fb: add ioctl to flip dc windows to nvmap handles

Erik Gilling <konkers@android.com>
video: tegra: dc: increment syncpoints following window flips
video: tegra: drain syncpt waits on display disable

Original commit messages:
**
video: tegra: dc: use nvhost driver for host1x power management

Incrementing the frame done syncpoint value from the display interrupt
requires that the host module is powered on. As the syncpoint state is
saved and restored automatically by the host driver a cpu increment of
a syncpoint in the powered down state will be lost.

Also adds checks for host module being powered.
**
video: tegra: fb: add ioctl to flip dc windows to nvmap handles

tegra user-space graphics drivers may allocate framebuffers using
nvmap rather than rendering to the common framebuffer, this may
be done to support deeper buffer pipelining, color formats
and pixel layouts other than the initial bootup framebuffer,
etc.

to use this ioctl, a caller must first specify an nvmap fd
which is already open in the calling process so that the
subsequent flip ioctls may be properly validated. flips are performed
asynchronously, with flip completion notifications provided back to
the caller via the host1x syncpoint mechanism

based on earlier changes made by Antti Hatala <ahatala@nvidia.com>
and Erik Gilling <konkers@android.com>

Change-Id: I4e8a8bb92085a485d65fd87d89112b2969ee37ff
Signed-off-by: Gary King <gking@nvidia.com>