msm: kgsl: Don't go to slumber if active_count is non zero

If active_cnt happens to be set when we go into
kgsl_early_suspend_driver() then don't go to SLUMBER.  This
avoids trouble if we come back and try to access the
hardware while it is off.

Change-Id: Ic0dedbadb13514a052af6199c8ad1982d7483b3f
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>