video: tegra: fb: intimate fbcon to blank/unblank

video: tegra: fb: intimate fbcon to blank/unblank

Upon a hotplug/unplug, intimate fbcon to unblank or
blank accordingly. This helps in keeping dc and fbcon
in sync.

bug 1693204

Change-Id: I96b83bd8420e68ebb6048d50d9d9a422cd1fb706
Signed-off-by: Naveen Kumar S <nkumars@nvidia.com>
Reviewed-on: http://git-master/r/820409
(cherry picked from commit 3a5c4678905a299e6ffadfaa8fab56bf4b29255d)
Reviewed-on: http://git-master/r/820822
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Animesh Kishore <ankishore@nvidia.com>
Reviewed-by: Venu Byravarasu <vbyravarasu@nvidia.com>