msm: kgsl: Call sync_fence_log only if CONFIG_SYNC is defined

Add a wrapper kgsl_sync_fence_log around sync_fence_log.
This helps get rid of compilation error if CONFIG_SYNC is
not defined.

CRs-Fixed: 748003
Change-Id: I20d9c0e4b449cb2352274b5f4062300d5562bae6
Signed-off-by: Harshdeep Dhatt <hdhatt@codeaurora.org>