dvb: Fix string copy wiht strlen() argument

This is a new warning introduced by gcc 8

We already check just before that we have enough space, just do a regular
memcpy with the full string size.

camswclient.c:87:3: error: ‘strncpy’ specified bound depends on the length of the source argument [-Werror=stringop-overflow=]
diff --git a/sys/dvb/camswclient.c b/sys/dvb/camswclient.c
index 2020569..19774e5 100644
--- a/sys/dvb/camswclient.c
+++ b/sys/dvb/camswclient.c
@@ -84,7 +84,7 @@
   addr.sun_family = AF_UNIX;
-  strncpy (addr.sun_path, sock_path, strlen (sock_path));
+  memcpy (addr.sun_path, sock_path, strlen (sock_path) + 1);
   GST_INFO ("connecting to softcam socket: %s", sock_path);
   if ((client->sock = socket (PF_UNIX, SOCK_STREAM, 0)) < 0) {