drm/i915: Remove i915_reg.h from intel_dram.c
Make intel_dram.c free from including i915_reg.h.
v3: Move MEM_SS info reg to display instead of pcode header (Jani)
v2: Move mem config register to newly added pcode header (Jani)
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patch.msgid.link/20260205094341.1882816-9-uma.shankar@intel.com