drm/xe: Suppress printing of mode when running in non-sriov mode

The xe_sriov_probe_early() function prints the sriov pf/vf mode on
driver probe. When running in non-sriov mode, the below debug message
is seen.

"Running in none mode".

This print does not convey any information. This commit suppresses this
debug message and shows only when running in PF/VF mode.

Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Cc: Michał Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250116055617.20611-1-satyanarayana.k.v.p@intel.com