[SCSI] tgt: use KMEM_CACHE macro

This uses new KMEM_CACHE() macro instead of kmem_cache_create directly
to simplify slab cache creation.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

drivers/scsi/scsi_tgt_lib.c

@@ -621,9 +621,7 @@ static int __init scsi_tgt_init(void)
 {
 	int err;
 
-	scsi_tgt_cmd_cache = kmem_cache_create("scsi_tgt_cmd",
-					       sizeof(struct scsi_tgt_cmd),
-					       0, 0, NULL);
+	scsi_tgt_cmd_cache =  KMEM_CACHE(scsi_tgt_cmd, 0);
 	if (!scsi_tgt_cmd_cache)
 		return -ENOMEM;