drm/amd/display: Change Navi14's DWB flag to 1

[Why]
DWB (Display Writeback) flag needs to be enabled as 1, or system
will throw out a few warnings when creating dcn20 resource pool.
Also, Navi14's dwb setting needs to match Navi10's,
which has already been set to 1.

[How]
Change value of num_dwb from 0 to 1.
Signed-off-by: NZhan Liu <zhan.liu@amd.com>
Reviewed-by: NNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c

@@ -814,7 +814,7 @@ static const struct resource_caps res_cap_nv14 = {
 		.num_audio = 6,
 		.num_stream_encoder = 5,
 		.num_pll = 5,
-		.num_dwb = 0,
+		.num_dwb = 1,
 		.num_ddc = 5,
 };