drm/xe: Introduce the RPa information

RPa is the Achievable frequency, defined by PCODE at runtime
based on multiple running conditions.

v2: Remove RPA_MASK from i915 file

Cc: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Reviewed-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241220152936.623627-1-rodrigo.vivi@intel.com


Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>