disp: msm: sde: add VM files for SDE

Add VM layer files to handle VM specific operations
for primary and secondary VM's. They interact with
Hypervisor RM modules to LEND/ACCEPT/RELEASE/RECLAIM
HW resources. They also handle notifications for each
of the above Hyp RM operations to acquire and update
the SDE software states.

Change-Id: I5982f4bf56550dc464797c62cb356be39925b21c
Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>