msm: kgsl: Restrict max cache ways allowed for VFD

Restrict max cache ways allowed for VFD to 2. This is to
increase performance by restricting VFD's cache access,
so that LRZ and other data get evicted less.

Change-Id: Icd4486c0f45c681a9dde7c946c53bd618431b631
Signed-off-by: Tarun Karra <tkarra@codeaurora.org>