A new VTY node was added in commit [1], but bsc_vty_go_parent() was
not updated. Because of that, commands following the MGW node may
crash osmo-bsc. In the example below:
network
network country code 901
mobile network code 70
...
mgw 0
remote-ip 127.0.0.1
local-ip 127.0.0.1
periodic location update 30
the 'periodic location update 30' will trigger a segfault:
(gdb) bt
#0 0x00005555555dfc09 in cfg_net_per_loc_upd ()
#1 0x00007ffff7af6c3f in cmd_execute_command_strict () from /usr/local/lib/libosmovty.so.9
#2 0x00007ffff7af6f1c in config_from_file () from /usr/local/lib/libosmovty.so.9
#3 0x00007ffff7afd4e1 in vty_read_config_filep () from /usr/local/lib/libosmovty.so.9
#4 0x00007ffff7afe375 in vty_read_config_file () from /usr/local/lib/libosmovty.so.9
#5 0x0000555555579616 in bsc_network_configure ()
#6 0x000055555557a352 in main ()
because vty->index would be NULL after returning from the MGW node.
Fix this by adding the missing case to bsc_vty_go_parent().
Change-Id: Id3050ff7e2402c33ee76c7bf0cc83603c0cc6dfc
Fixes: [1] 8d22e68706
(cherry picked from commit 57800ec48e)