drm/amd/display: Fix warning comparing pointer to 0

Avoid pointer type value compared with 0 to make code clear.

./drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_dpmm/dml2_dpmm_factory.c:24:12-13: WARNING comparing pointer to 0.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=9458Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dml2/dml21/src/dml2_dpmm/dml2_dpmm_factory.c

@@ -21,7 +21,7 @@ bool dml2_dpmm_create(enum dml2_project_id project_id, struct dml2_dpmm_instance
 {
 	bool result = false;
 
-	if (out == 0)
+	if (!out)
 		return false;
 
 	memset(out, 0, sizeof(struct dml2_dpmm_instance));