drm/i915/lrc: User PXP contexts requires runalone bit in lrc

On Meteorlake onwards, HW specs require that all user contexts that
run on render or compute engines and require PXP must enforce
run-alone bit in lrc. Add this enforcement for protected contexts.

Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Vivaik Balasubrawmanian <vivaik.balasubrawmanian@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230917211933.1407559-4-alan.previn.teres.alexis@intel.com