ARM: dts: msm: Enable BIMC based GPU bus governor for MSM8994

Use generic BIMC governor infrastructure to activate GPU bus
bandwidth governor. Exclude VBIF based GPU bus votes from the bus
vote table, but keep ocmem votes there.

Change-Id: I78be546a4dbe9ebd63b51215015c158a27918273
Signed-off-by: Vladimir Razgulin <vrazguli@codeaurora.org>