layer23: Use osmo_strlcpy() to avoid non-terminated strings

settings.c:191:2: warning: ‘strncpy’ output may be truncated copying 15 bytes from a string of length 15 -Wstringop-truncation]
  strncpy(set->imeisv, set->imei, 15);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  CC       subscriber.o
  CC       support.o
  CC       transaction.o
  CC       vty_interface.o
  CC       voice.o
  CC       mncc_sock.o
  CC       primitives.o
mncc_sock.c: In function ‘osmo_unixsock_listen’:
mncc_sock.c:318:2: warning: ‘strncpy’ specified bound 108 equals destination size [-Wstringop-truncation]
  strncpy(local.sun_path, path, sizeof(local.sun_path));
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  CC       script_lua.o
vty_interface.c: In function ‘cfg_gps_device’:
vty_interface.c:1144:2: warning: ‘strncpy’ specified bound 32 equals destination size [-Wstringop-truncation]
  strncpy(g.device, argv[0], sizeof(g.device));
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  AR       libmobile.a

Change-Id: Id52978f3bf7a8abea62237d7c32f8f87e1bb34a1

src/host/layer23/src/mobile/mncc_sock.c

@@ -315,7 +315,7 @@ int osmo_unixsock_listen(struct osmo_fd *bfd, int type, const char *path)
 	}
 
 	local.sun_family = AF_UNIX;
-	strncpy(local.sun_path, path, sizeof(local.sun_path));
+	osmo_strlcpy(local.sun_path, path, sizeof(local.sun_path));
 	local.sun_path[sizeof(local.sun_path) - 1] = '\0';
 	unlink(local.sun_path);
 

src/host/layer23/src/mobile/settings.c

@@ -189,7 +189,7 @@ int gsm_random_imei(struct gsm_settings *set)
 	sprintf(rand + 8, "%07d", layer23_random() % 10000000);
 
 	strcpy(set->imei + 15 - digits, rand + 15 - digits);
-	strncpy(set->imeisv, set->imei, 15);
+	osmo_strlcpy(set->imeisv, set->imei, 15);
 
 	return 0;
 }

src/host/layer23/src/mobile/vty_interface.c

@@ -1141,7 +1141,7 @@ DEFUN(cfg_gps_device, cfg_gps_device_cmd, "gps device DEVICE",
 	"GPS receiver\nSelect serial device\n"
 	"Full path of serial device including /dev/")
 {
-	strncpy(g.device, argv[0], sizeof(g.device));
+	osmo_strlcpy(g.device, argv[0], sizeof(g.device));
 	g.device[sizeof(g.device) - 1] = '\0';
 	g.gps_type = GPS_TYPE_SERIAL;
 	if (g.enable) {