[PATCH] drm/amd/display: use NULL instead of using plain integer as pointer

[Haowen Bai]

This fixes the following sparse warnings:
drivers/gpu/drm/amd/amdgpu/../display/dc/dce112/dce112_resource.c:865:16: 
warning: Using
plain integer as NULL pointer

Signed-off-by: Haowen Bai <baihao...@meizu.com>
---
 drivers/gpu/drm/amd/display/dc/dce112/dce112_resource.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dce112/dce112_resource.c 
b/drivers/gpu/drm/amd/display/dc/dce112/dce112_resource.c
index ee55cda..560da6c 100644
--- a/drivers/gpu/drm/amd/display/dc/dce112/dce112_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dce112/dce112_resource.c
@@ -862,7 +862,7 @@ static struct clock_source *find_matching_pll(
                return NULL;
        }
 
-       return 0;
+       return NULL;
 }
 
 static enum dc_status build_mapped_resource(
-- 
2.7.4