clk: Provide dummy clk_unregister()

While there's no actual implementation behind it having the call to use
in drivers makes them feel neater from a driver author point of view. An
actual implementation can wait for someone who needs to use the function
in a real system.

Signed-off-by: Mark Brown <[e-mail]>
[[e-mail]: void return type instead of int -EINVAL]
Signed-off-by: Mike Turquette <[e-mail]>

drivers/clk/clk.c

···
 }
 EXPORT_SYMBOL_GPL(clk_register);
 
+/**
+ * clk_unregister - unregister a currently registered clock
+ * @clk: clock to unregister
+ *
+ * Currently unimplemented.
+ */
+void clk_unregister(struct clk *clk) {}
+EXPORT_SYMBOL_GPL(clk_unregister);
+
 /***        clk rate change notifiers        ***/
 
 /**

include/linux/clk-provider.h

···
  */
 struct clk *clk_register(struct device *dev, struct clk_hw *hw);
 
+void clk_unregister(struct clk *clk);
+
 /* helper functions */
 const char *__clk_get_name(struct clk *clk);
 struct clk_hw *__clk_get_hw(struct clk *clk);