msm: vidc: aggregate OCMEM bandwidth for low-power mode

OCMEM voting was hardcoded during low-power mode. This would
break low power mode if underneath code is modified. This
commit aggregates the load programatically.

Change-Id: Ibe1252e7795227b3642033b2577a01c04032ea6a
Signed-off-by: Ashray Kulkarni <ashrayk@codeaurora.org>