drm/amd/display: Fix memory leak in dcn21_clock_source_create

When dcn20_clk_src_construct() fails, we need to release clk_src.

Fixes: 6f4e636 ("drm/amd/display: Add Renoir resource (v2)")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Author: Yuuoniy

drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c

@@ -997,6 +997,7 @@ static struct clock_source *dcn21_clock_source_create(
 		return &clk_src->base;
 	}
 
+	kfree(clk_src);
 	BREAK_TO_DEBUGGER();
 	return NULL;
 }