BACKPORT: UPSTREAM: drm/i915/mtl+: Disable DP/DSC SF insertion at EOL WA

Disable the workaround inserting an SF symbol between the last DSC EOC
symbol and the subsequent BS symbol. The WA is enabled by default -
based on the register's reset value - and Bspec requires disabling it
explicitly. Bspec doesn't provide an actual WA ID for this.

Bspec: 50054, 65448, 68849

Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Change-Id: If583ba0823cd95b5da0b72d92f5e4c891a409590
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240129175533.904590-6-imre.deak@intel.com
(cherry picked from commit 7e3025c6 https://anongit.freedesktop.org/git/drm-intel.git

 drm-intel-next)
Signed-off-by: Charlton Lin <charlton.lin@intel.com>

Conflicts:
	drivers/gpu/drm/i915/display/intel_display.c

BUG=b:332903004, b:322223603
TEST=Verify Dell U3224KB 6k mode on Rex using UHBR, MST encoder, Big Joiner, and DSC

Change-Id: Ie07668afefe272538977bff20dc75ce98c32d3d0
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/5498873


Reviewed-by: Manasi Navare <navaremanasi@chromium.org>
Commit-Queue: Manasi Navare <navaremanasi@chromium.org>
Tested-by: Charlton Lin <charlton.lin@intel.com>
Signed-off-by: Rakshith M O <rakshith.m.o@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/5802880


Signed-off-by: Hubert Mazur <hmazur@google.com>