drm/xe/hw_error: Use HW_ERR prefix in log

drm/xe/hw_error: Use HW_ERR prefix in log

Hardware errors should be logged with HW_ERR prefix. Make them
consistent with existing logs.

Fixes: 01aab7e1c9d4 ("drm/xe/xe_hw_error: Add support for PVC SoC errors")
Signed-off-by: Raag Jadav <raag.jadav@intel.com>
Reviewed-by: Riana Tauro <riana.tauro@intel.com>
Link: https://patch.msgid.link/20260602044919.702209-5-raag.jadav@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
(cherry picked from commit ad60a618c49fef07d1860bfb1091140d29f5eddb)
Signed-off-by: Matthew Brost <matthew.brost@intel.com>