drm/xe: Use GT oriented message to report engine activity error

We are enabling/disabling engine activity on per-GT basis, so any
errors should be also reported per GT, like:

 [ ] xe 0000:00:02.0: [drm] GT0: PF: Failed to enable engine activity function stats (-ENOSPC)
 [ ] xe 0000:00:02.0: [drm] GT1: PF: Failed to enable engine activity function stats (-ENOSPC)

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Cc: Riana Tauro <riana.tauro@intel.com>
Reviewed-by: Riana Tauro <riana.tauro@intel.com>
Link: https://lore.kernel.org/r/20250414202347.1909-2-michal.wajdeczko@intel.com