i915: Add DMC v2.18 for ADLP

Just as done with HuC in commit 51fff4e69b ("i915: Add versionless HuC
files for current platforms"), we are now starting to move away from
versioning filenames. Next updates for platforms already moved to the
new convention will just replace the blob files and update the WHENCE
file to reflect the new version.

Notes for this DMC release:

  1. Bug-fixes for latest release.

Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>

WHENCE

@@ -4624,6 +4624,9 @@ Version: DMC API/APB ver 2 release 14 for Alderlake P
 File: i915/adlp_dmc_ver2_16.bin
 Version: DMC API/APB ver 2 release 16 for Alderlake P
 
+File: i915/adlp_dmc.bin
+Version: DMC API/APB ver 2 release 18 for Alderlake P
+
 File: i915/adlp_guc_62.0.3.bin
 Version: GuC API/APB ver 62.0.3 for Alderlake P