drm/xe: Improve unexpected state error messages

Include G2H handler name when an unexpected error state messages.

v6:
- Use xe_gt_err (Michal)
- Print runnable state (John H)

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240611144053.2805091-7-matthew.brost@intel.com