gma500: Use DEFINE_SPINLOCK() for spinlock

spinlock can be initialized automatically with DEFINE_SPINLOCK()
rather than explicitly calling spin_lock_init().

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Guobin Huang <huangguobin4@huawei.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1617710114-48071-1-git-send-email-huangguobin4@huawei.com

Author: Guobin Huang

drivers/gpu/drm/gma500/power.c

@@ -36,7 +36,7 @@
 #include <linux/pm_runtime.h>
 
 static struct mutex power_mutex;	/* Serialize power ops */
-static spinlock_t power_ctrl_lock;	/* Serialize power claim */
+static DEFINE_SPINLOCK(power_ctrl_lock);	/* Serialize power claim */
 
 /**
  *	gma_power_init		-	initialise power manager
@@ -55,7 +55,6 @@ void gma_power_init(struct drm_device *dev)
 	dev_priv->display_power = true;	/* We start active */
 	dev_priv->display_count = 0;	/* Currently no users */
 	dev_priv->suspended = false;	/* And not suspended */
-	spin_lock_init(&power_ctrl_lock);
 	mutex_init(&power_mutex);
 
 	if (dev_priv->ops->init_pm)