drm/amd/display: build dcn21 blocks

Enable the building of dcn21 support.
Acked-by: NHarry Wentland <harry.wentland@amd.com>
Signed-off-by: NBhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/Makefile

@@ -37,6 +37,9 @@ endif
 ifdef CONFIG_DRM_AMD_DC_DCN1_0
 DC_LIBS += dcn10 dml
 endif
+ifdef CONFIG_DRM_AMD_DC_DCN2_1
+DC_LIBS += dcn21
+endif
 
 DC_LIBS += dce120