drm/msm/sde: support bw vote routing through apps and disp rsc

Display has its own rsc. It can route the different displays
bandwidth vote through either apps rsc, display rsc or combine
method. This patch adds the dynamic routing support through
debugfs and dtsi configuration for bandwidth vote routing.

Change-Id: I70cfee784951fd4becf5e817606889e830a134e9
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>