drm/amd/display: Have risk for memory exhaustion

In dcn*_clock_source_create when dcn*_clk_src_construct fails allocated
clk_src needs release. A local attack could use this to cause memory
exhaustion.

Signed-off-by: LongJun Tang <tanglongjun@kylinos.cn>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn31/dcn31_resource.c

@@ -1629,6 +1629,7 @@ static struct clock_source *dcn31_clock_source_create(
 		return &clk_src->base;
 	}
 
+	kfree(clk_src);
 	BREAK_TO_DEBUGGER();
 	return NULL;
 }