msm: kgsl: Clear correct priv bit in coresight disable

adreno_coresight_disable can be called for coresight
CX as well as for GX, however code was clearing GX
bit always. Clear correct bit according to cs_id.

Change-Id: If6dcffb492a21ca4f319f01c7ea4c6aec2ea6dcc
Signed-off-by: Prakash Kamliya <pkamliya@codeaurora.org>