drm/i915/guc: Add selftest for a hung GuC

Add a test to check that the hangcheck will recover from a submission
hang in the GuC.

Signed-off-by: Rahul Kumar Singh <rahul.kumar.singh@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220728182616.2417491-1-John.C.Harrison@Intel.com