pwm: brcmstb: Utilize appropriate clock APIs in suspend/resume

The suspend/resume functions currently utilize
clk_disable()/clk_enable() respectively which may be no-ops with certain
clock providers such as SCMI. Fix this to use clk_disable_unprepare()
and clk_prepare_enable() respectively as we should.

Fixes: 3a9f5957 ("pwm: Add Broadcom BCM7038 PWM controller support")
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/pwm-brcmstb.c

@@ -264,7 +264,7 @@ static int brcmstb_pwm_suspend(struct device *dev)
 {
 	struct brcmstb_pwm *p = dev_get_drvdata(dev);
 
-	clk_disable(p->clk);
+	clk_disable_unprepare(p->clk);
 
 	return 0;
 }
@@ -273,7 +273,7 @@ static int brcmstb_pwm_resume(struct device *dev)
 {
 	struct brcmstb_pwm *p = dev_get_drvdata(dev);
 
-	clk_enable(p->clk);
+	clk_prepare_enable(p->clk);
 
 	return 0;
 }