pwm: clps711x: Drop driver local locking

The pwm core serializes calls to .apply(), so the spinlock adds no
additional protection. Disabling the irq is also irrelevant as the driver
isn't an atomic one and so the callbacks cannot be called from atomic
context.

Signed-off-by: Uwe Kleine-König <[e-mail]>
Link: https://lore.kernel.org/r/d4931dc[e-mail]
Signed-off-by: Uwe Kleine-König <[e-mail]>

drivers/pwm/pwm-clps711x.c

···
 struct clps711x_chip {
 	void __iomem *pmpcon;
 	struct clk *clk;
-	spinlock_t lock;
 };
 
 static inline struct clps711x_chip *to_clps711x_chip(struct pwm_chip *chip)
···
 	struct clps711x_chip *priv = to_clps711x_chip(chip);
 	/* PWM0 - bits 4..7, PWM1 - bits 8..11 */
 	u32 shift = (pwm->hwpwm + 1) * 4;
-	unsigned long flags;
 	u32 pmpcon, val;
 
 	if (state->polarity != PWM_POLARITY_NORMAL)
···
 	else
 		val = 0;
 
-	spin_lock_irqsave(&priv->lock, flags);
-
 	pmpcon = readl(priv->pmpcon);
 	pmpcon &= ~(0xf << shift);
 	pmpcon |= val << shift;
 	writel(pmpcon, priv->pmpcon);
-
-	spin_unlock_irqrestore(&priv->lock, flags);
 
 	return 0;
 }
···
 		return PTR_ERR(priv->clk);
 
 	chip->ops = &clps711x_pwm_ops;
-
-	spin_lock_init(&priv->lock);
 
 	return devm_pwmchip_add(&pdev->dev, chip);
 }