drm/amd/display: Add Vega20 config. support

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Jerry (Fangzhi) Zuo <Jerry.Zuo@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/Kconfig

@@ -40,4 +40,13 @@ config DRM_AMD_DC_VEGAM
         help
          Choose this option if you want to have
          VEGAM support for display engine
+
+config DRM_AMD_DC_VG20
+	bool "Vega20 support"
+	depends on DRM_AMD_DC
+	help
+		Choose this option if you want to have
+		Vega20 support for display engine
+
+
 endmenu