route/vlan: fix memory corruption in rtnl_link_vlan_set_egress_map
route/vlan: fix memory corruption in rtnl_link_vlan_set_egress_map

If you set more than four entries for the vlan egress map a memory
corruption occurs because the reallocation does not reserve memory
for more than four.

Fixes: a7469ce758fac3631df6ce72eb3f89150070e7f8

https://github.com/thom311/libnl/pull/155

[thaller@redhat.com: squashed commits and updated commit message]

thom311/libnl,greearb/libnl-ct,thom311/libnl,greearb/libnl-ct,greearb/libnl-ct,thom311/libnl