Remove some redundant kernel messages as we deduce a hung GPU and
capture the error state.

v2: Fix "hang" vs "no progress" message whilst I was there
v3: s/snprintf/scnprintf/
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1467618513-4966-2-git-send-email-chris@chris-wilson.co.ukReviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>