dt-bindings: clock: Add support for clock ids for SCUBA

Add clock IDs for GCC/DISPCC/VIDEOCC for clients to be able to request
for clocks from these clock controllers.

Change-Id: I2653af6e87a5dc939743f5f776bbc3e3c5703073
Signed-off-by: Taniya Das <tdas@codeaurora.org>