ARM: dts: msm: Use bw_vbif as GPU governor on MSM8909

Use bw_vbif as governor on MSM8909 instead of bw_hwmon
for GPU and also remove unused bandwidth voting levels
for bw_tbl.

Change-Id: Ic6df6e8ef867965281ef083f7d81ad62bdb3e7c0
Signed-off-by: Deepak Kumar <dkumar@codeaurora.org>