video: tegra: fbcon: remove dangling pointer in VC

video: tegra: fbcon: remove dangling pointer in VC

Remove dangling mode pointer in virtual consoles by updating
all VCs upon new modelist event.

bug 200009711

Change-Id: If4cc5622f39f864943b3715342c8d3d8c1857ba1
Signed-off-by: Jong Kim <jongk@nvidia.com>
Reviewed-on: http://git-master/r/432321
(cherry picked from commit c7ed2def2b13fb3af95ed778e353dc902f5ab47e)
Reviewed-on: http://git-master/r/435919
Reviewed-by: Automatic_Commit_Validation_User
GVS: Gerrit_Virtual_Submit
Reviewed-by: Pankaj Dabade <pdabade@nvidia.com>
Reviewed-by: Jon Mayo <jmayo@nvidia.com>