drm/xe: Check skip_guc_pc before setting SLPC flag

drm/xe: Check skip_guc_pc before setting SLPC flag

Don't set SLPC GuC feature ctl flag if skip_guc_pc is true.

v2: Skip the freq related sysfs creation as well (Badal)
v3: Remove unnecessary parenthesis (Lucas)

Fixes: 975e4a3795d4 ("drm/xe: Manually setup C6 when skip_guc_pc is set")
Fixes: bef52b5c7a19 ("drm/xe: Create a xe_gt_freq component for raw management and sysfs")
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Link: https://lore.kernel.org/r/20240108225842.966066-1-vinay.belgaumkar@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>