msm: kgsl: Add rscc registers to a650 snapshot

A650 has new rscc registers so dump them in snapshot.
Also, dump them before checking whether gx is on
because rscc registers are in cx.

Change-Id: Iad8063e6bd3a806d3e7cd1d637e451cf6e0d9d55
Signed-off-by: Harshdeep Dhatt <hdhatt@codeaurora.org>