drm/i915/guc: Check for wedged before doing stuff

A fault injection probe test hit a BUG_ON in a GuC error path. It
showed that the GuC code could potentially attempt to do many things
when the device is actually wedged. So, add a check in to prevent that.

v2: Use intel_gt_is_wedged instead of testing bits directly in the
GuC submission code (review feedback from Tvrtko).

Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211221210212.1438670-1-John.C.Harrison@Intel.com