drm/xe/execlist: Remove leftover printk messages

Those look like leftover debug and are not even being used. If they were
real debug/info, they should be using the drm helpers.

Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>