msm: kgsl: Wait for the active_count in kgsl_release()

It is possible that a context can be successfully destroyed and
kgsl_release() called by an exiting application before the kernel
threads have released all the users of the active count.  Instead
of immediately calling BUG_ON() in kgsl_release() when the active
count is unexpected, wait a second to give the others time to
finish up.  If after a second the active count still hasn't gone
where we need it to then we can assume driver error and BUG_ON().

To accomplish this, remodel kgsl_active_count_wait() to take a
active_count value to "wait" for.

Change-Id: Ic0dedbadcc7d0714ea14f25e2a43715e2e12c041
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>