[SCSI] megaraid/megaraid_mm.c: fix a NULL pointer dereference

This patch fixes a NULL pointer dereference spotted by the Coverity
checker.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

drivers/scsi/megaraid/megaraid_mm.c

@@ -898,10 +898,8 @@ mraid_mm_register_adp(mraid_mmadp_t *lld_adp)
 
 	adapter = kmalloc(sizeof(mraid_mmadp_t), GFP_KERNEL);
 
-	if (!adapter) {
-		rval = -ENOMEM;
-		goto memalloc_error;
-	}
+	if (!adapter)
+		return -ENOMEM;
 
 	memset(adapter, 0, sizeof(mraid_mmadp_t));