linux-firmware/i915: Restore DMC 1.23

1.26 is the stable and recommended firmware for Skylake.
However one conflict in i915 accidentally restored 1.23
making that the default in some kernel out there.

So, let's restore this 1.23 here.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97182
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

WHENCE

@@ -3127,6 +3127,7 @@ Licence: Redistributable. See LICENCE.cavium for details
 
 Driver: i915 -- Intel Integrated Graphics driver
 
+File: i915/skl_dmc_ver1_23.bin
 File: i915/skl_dmc_ver1_26.bin
 File: i915/skl_dmc_ver1.bin
 Version: DMC API/ABI ver 1 - release 26 for Skylake