drm/msm: Fix kernel address issue of profile buffer

Current DRM adds offset when making IOVA but failed to add it when
making kernel address. This makes DRM write queue_s and submit_s to
wrong place if the profile buffer is not at the head of
a chunk of buffer.

Change-Id: I5af9c3050f4c6c5e0a54ed495bf79053f08f0bab
Signed-off-by: Kasin Li <donglil@codeaurora.org>