drm/i915/vrr: Add compute config for DC Balance params

drm/i915/vrr: Add compute config for DC Balance params

Compute DC Balance parameters and tunable params based on
experiments.

--v2:
- Document tunable params. (Ankit)

--v3:
- Add line spaces to compute config. (Ankit)
- Remove redundancy checks.

--v4:
- Separate out conpute config to separate function.
- As all the valuse are being computed in scanlines, and slope
is still in usec, convert and store it to scanlines.

--v5:
- Update and add comments for slope calculation. (Ankit)
- Update early return conditions for dc balance compute. (Ankit)

--v6:
- Early return condition simplified for dc balance compute config. (Ankit)
- Make use of pipe restrictions to this patch. (Ankit)

--v7:
- Separate out PIPE_A and PIPE_B restrictions to other patch.(Ankit)

Signed-off-by: Mitul Golani <mitulkumar.ajitkumar.golani@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patch.msgid.link/20251223104542.2688548-8-mitulkumar.ajitkumar.golani@intel.com