msm: kgsl: Allow access to QDSS only when coresight is enabled

Allocate and map QDSS region only when coresight is enabled.
Remove apb_pclk from the clock list when coresight is disabled.

Change-Id: I9be6e1abeab26af3abe9196b87368ceba9a98d01
Signed-off-by: Harshitha Sai Neelati <hsaineel@codeaurora.org>