msm: kgsl: Prevent dual ownership of GMU counters

The last two XO clock-based GMU power counters are
owned by the GMU firmware. Mark them as broken to
prevent KGSL from using them and causing dual
ownership problems.

Change-Id: I481f850153cbbce7ccf149e032c68e37cc112dac
Signed-off-by: Kyle Piefer <kpiefer@codeaurora.org>