drm/i915/vdsc: Add bpc check in intel_dsc_compute_params

DSC does not support bpc under 8 according to DSC 1.2a Section 2
Requirements. Return an error if that happens to be the case.

--v2
-should be bit_per_component [Mitul/Chaitanya]
-Add reference to this restriction [Chaitanya]

--v3
-Add the bpc in which we see this warning [Jani]

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240926081327.1409518-2-suraj.kandpal@intel.com