s390/pci: use kmem_cache_zalloc instead of kmem_cache_alloc/memset

Using kmem_cache_zalloc() instead of kmem_cache_alloc() and memset().

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 27b4c17..fddf847 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -249,10 +249,9 @@
 	if (zdev->fmb)
 		return -EINVAL;
 
-	zdev->fmb = kmem_cache_alloc(zdev_fmb_cache, GFP_KERNEL);
+	zdev->fmb = kmem_cache_zalloc(zdev_fmb_cache, GFP_KERNEL);
 	if (!zdev->fmb)
 		return -ENOMEM;
-	memset(zdev->fmb, 0, sizeof(*zdev->fmb));
 	WARN_ON((u64) zdev->fmb & 0xf);
 
 	args.fmb_addr = virt_to_phys(zdev->fmb);