Fix problem with some strings not being null-terminated,
by using the vec_terminate_c_string macro in two places.
The problem was found using AddressSanitizer.
(Also make sure indentation is OK for those changes.)
Ticket: VPP-1772
Type: fix
Signed-off-by: Elias Rudberg <elias.rudberg@bahnhof.net>
Change-Id: Ib7826e3c322e58b649e2d7f6053786da618a5e9e