msm: kgsl: Remove some spammy log messages

We should not be printing a log message every time the KGSL device
is opened, nor should we print a log message for properties that
are intentionally not available on some targets.

Change-Id: Ic0dedbadb75338e8b5fa7a414733160de5049fa9
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>