isdn: use strlcpy() instead strcpy()

I don't think the in-kernel drivers ever hit this strcpy() so this
doesn't change how the code works.  But strlcpy() is safer.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/isdn/sc/event.c b/drivers/isdn/sc/event.c
index 717003a..833d96c 100644
--- a/drivers/isdn/sc/event.c
+++ b/drivers/isdn/sc/event.c
@@ -57,7 +57,7 @@
 			memcpy(&cmd.parm.setup, Data, sizeof(cmd.parm.setup));
 			break;
 		default:
-			strcpy(cmd.parm.num, Data);
+			strlcpy(cmd.parm.num, Data, sizeof(cmd.parm.num));
 		}
 	}