soc: qcom: hgsl: Support DBQ count upto 9

3 DBQs can be assigned to one GVM and have different priority such as
low, medium and high based on the context priority.

Change-Id: Ie7ab4c6837528954ca56033bb2e7c515a16b27f8
Signed-off-by: Thomas (Wonyoung) Yun <wyun@codeaurora.org>