msm: kgsl: Wrap IBs with SET_MARKER packets on A6XX

Currently, these packets will only be inserted if preemption
is enabled. However, these packets are needed regardless of
preemption. For example, these packets are used for SPTPRAC
power collapse feature. So always insert these packets in
the ringbuffer.

Change-Id: Idb854797736876b5875b21455a337c8bf1145d36
Signed-off-by: Harshdeep Dhatt <hdhatt@codeaurora.org>