drm/msm: Drop chatty trace

It is somewhat redundant with the gpu tracepoints, and anyways not too
useful to justify spamming the log when debug traces are enabled.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Jordan Crouse <jcrouse@codeaurora.org>
Reviewed-by: Kristian H. Kristensen <hoegsberg@google.com>
Signed-off-by: Rob Clark <robdclark@chromium.org>