drm/i915/dram: Add field ecc_impacting_de_bw

drm/i915/dram: Add field ecc_impacting_de_bw

Starting with Xe3p_LPD, we now have a new field in MEM_SS_INFO_GLOBAL
that indicates whether the memory has enabled ECC that limits display
bandwidth.  Add the field ecc_impacting_de_bw to struct dram_info to
contain that information and set it appropriately when probing for
memory info.

Currently there are no instructions in Bspec on how to handle that case,
so let's throw a warning if we ever find such a scenario.

v2:
  - s/ecc_impacting_de/ecc_impacting_de_bw/ to be more specific. (Matt
    Atwood)
  - Add warning if ecc_impacting_de_bw is true, since we currently do
    not have instructions on how to handle it. (Matt Roper)
v3:
  - Check on ecc_impacting_de_bw for the warning only for Xe3p_LPD and
    beyond.
  - Change warning macro from drm_WARN_ON_ONCE() to drm_WARN_ON().

Bspec: 69131
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Matt Atwood <matthew.s.atwood@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patch.msgid.link/20251103-xe3p_lpd-basic-enabling-v3-15-00e87b510ae7@intel.com
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>