[Why&How]
DCN301 does not have FAMS hence the workaround needed on other DCN3x
variants related to OTG min/max selector programming is not applicable for it.
Hence isolate it and have it use the old sequence without workaround.

Fixes: 1598fc57 ("drm/amd/display: Program OTG vtotal min/max selectors unconditionally for DCN1+")
Reviewed-by: Swapnil Patel <swapnil.patel@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>