clk: mediatek: provide common clk init function for infrasys

Provide common clk init function for infrasys that defaults to topckgen
driver if clock-parent is not defined. This is the case for upstream
DTSI that doesn't provide this entry.

This is needed for infracfg driver that will make use of the unified
gates + muxes implementation.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
diff --git a/drivers/clk/mediatek/clk-mtk.h b/drivers/clk/mediatek/clk-mtk.h
index 4423689..e9c8a52 100644
--- a/drivers/clk/mediatek/clk-mtk.h
+++ b/drivers/clk/mediatek/clk-mtk.h
@@ -266,6 +266,8 @@
 
 int mtk_common_clk_init(struct udevice *dev,
 			const struct mtk_clk_tree *tree);
+int mtk_common_clk_infrasys_init(struct udevice *dev,
+				 const struct mtk_clk_tree *tree);
 int mtk_common_clk_gate_init(struct udevice *dev,
 			     const struct mtk_clk_tree *tree,
 			     const struct mtk_gate *gates);