msm: kgsl: Dump the always on counter for a6xx interrupts

If an interrupt occurs while GX is off it is useful to read the always
on counter value to match the error with the GMU trace.

Change-Id: Ic0dedbad923e37ebcb9c19dc26b0023a2bd0613c
Signed-off-by: Hareesh Gundu <hareeshg@codeaurora.org>
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>