drm/i915/xehp: Handle new device context ID format

Xe_HP changes the format of the context ID from past platforms.

Signed-off-by: Stuart Summers <stuart.summers@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Matt Atwood <matthew.s.atwood@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210721223043.834562-9-matthew.d.roper@intel.com