clk: pwm: Migrate to clk_hw based OF and registration APIs

Now that we have clk_hw based provider APIs to register clks, we
can get rid of struct clk pointers while registering clks in
these drivers, allowing us to move closer to a clear split of
consumer and provider clk APIs.

Cc: Janusz Uzycki <[e-mail]>
Cc: Philipp Zabel <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/clk-pwm.c

···
 	struct pwm_device *pwm;
 	struct pwm_args pargs;
 	const char *clk_name;
-	struct clk *clk;
 	int ret;
 
 	clk_pwm = devm_kzalloc(&pdev->dev, sizeof(*clk_pwm), GFP_KERNEL);
···
 
 	clk_pwm->pwm = pwm;
 	clk_pwm->hw.init = &init;
-	clk = devm_clk_register(&pdev->dev, &clk_pwm->hw);
-	if (IS_ERR(clk))
-		return PTR_ERR(clk);
+	ret = devm_clk_hw_register(&pdev->dev, &clk_pwm->hw);
+	if (ret)
+		return ret;
 
-	return of_clk_add_provider(node, of_clk_src_simple_get, clk);
+	return of_clk_add_hw_provider(node, of_clk_hw_simple_get, &clk_pwm->hw);
 }
 
 static int clk_pwm_remove(struct platform_device *pdev)