drm/msm/sde: add FETCH_ACTIVE logic and set default group ID

New required programming in CTL. Fetch active informs the HW
of the active fetch pipes. Group ID informs HW of which VM owns
that CTL. Force this group ID to default/disabled until
virtualization support is enabled in SW.

Change-Id: Id9d68ae725a640893a4e347b69ad2b506a998f25
Signed-off-by: Steve Cohen <cohens@codeaurora.org>