msm: kgsl: Fix fence debug message lock sequence

When fences timeout then debug information is printed to logs.
Fence timing out from sync driver calls a callback into kgsl
driver to print additional information about fence. Sync point
timers timing out in kgsl driver calls fence driver to print
fence information which again calls back into kgsl driver. Due
to this callback the spin lock taken in the sync timeout thread
can lead to deadlock or double spin unlock calls. Simplify the
code by making sure that when kgsl driver calls fence driver
to print fence information then the fence driver does not
callback again into kgsl driver.

Conflicts:
        drivers/gpu/msm/kgsl.c

CRs-Fixed: 816579
Change-Id: I5fea94fdb03d5d8e400d220c01a5faee498b3f54
Signed-off-by: Shubhraprakash Das <sadas@codeaurora.org>