iommu/amd: Use DEFINE_SPINLOCK() for spinlock

Spinlock can be initialized automatically with DEFINE_SPINLOCK()
rather than explicitly calling spin_lock_init().
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Link: https://lore.kernel.org/r/20201228135112.28621-1-zhengyongjun3@huawei.comSigned-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/amd/iommu_v2.c

@@ -77,7 +77,7 @@ struct fault {
 };
 
 static LIST_HEAD(state_list);
-static spinlock_t state_lock;
+static DEFINE_SPINLOCK(state_lock);
 
 static struct workqueue_struct *iommu_wq;
 
@@ -938,8 +938,6 @@ static int __init amd_iommu_v2_init(void)
 		return 0;
 	}
 
-	spin_lock_init(&state_lock);
-
 	ret = -ENOMEM;
 	iommu_wq = alloc_workqueue("amd_iommu_v2", WQ_MEM_RECLAIM, 0);
 	if (iommu_wq == NULL)