drm/xe/guc: Prefer GT oriented asserts in submit code

For better diagnostics, use xe_gt_assert() instead of xe_assert().

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241107194741.2167-2-michal.wajdeczko@intel.com