clk: introduce clk_dev_binded

When support Clock Common Framework, U-Boot use dev for
clk tree information, there is no clk->parent. When
support composite clk, it contains mux/gate/divider,
but the mux/gate/divider is not binded with device.
So we could not use dev_get_uclass_priv to get the correct
clk_mux/gate/divider. So add clk_dev_binded to let
choose the correct method.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 7d748c9..39b3087 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -55,3 +55,11 @@
 {
 	return hw->dev->name;
 }
+
+bool clk_dev_binded(struct clk *clk)
+{
+	if (clk->dev && (clk->dev->flags & DM_FLAG_BOUND))
+		return true;
+
+	return false;
+}