drm/dp: Add quirk for Synaptics DSC throughput link-bpp limit

Some Synaptics MST branch devices have a problem decompressing a stream
with a compressed link-bpp higher than 12, if the pixel clock is higher
than ~50 % of the maximum throughput capability reported by the branch
device. The screen remains blank, or for some - mostly black content -
gets enabled, but may stil have jitter artifacts.

At least the following docking stations are affected, based on testing
both with any Intel devices or the UCD-500 reference device as a source:

- DELL WD19DCS, DELL WD19TB3, DELL WD22TB4
- ThinkPad 40AN
- HP G2

At least the following docking stations are free from this problem,
based on tests with a source/sink/mode etc. configuration matching the
test cases used above:

- DELL Dual Charge HD22Q, DELL WD25TB5
- ThinkPad 40B0
- Anker 565

All the affected devices have an older version of the Synaptics MST
branch device (Panamera), whereas all the non-affected docking stations
have a newer branch device (at least Synaptics Panamera with a higher HW
revision number and Synaptics Cayenne models). Add the required quirk
entries accordingly. The quirk will be handled by the i915/xe drivers in
a follow-up change.

The latest firmware version of the Synaptics branch device for all the
affected devices tested above is 5.7 (as reported at DPCD address
0x50a/0x50b). For the DELL devices this corresponds to the latest
01.00.14.01.A03 firmware package version of the docking station.

v2:
- Document the DP_DPCD_QUIRK_DSC_THROUGHPUT_BPP_LIMIT enum.
- Describe the quirk in more detail in the dpcd_quirk_list.
v3:
- s/Panarema/Panamera in the commit log.

Cc: dri-devel@lists.freedesktop.org
Reported-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reported-and-tested-by: Swati Sharma <swati2.sharma@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://lore.kernel.org/r/20250930182450.563016-2-imre.deak@intel.com

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