"maxname" is the size of the buffer which also includes the "null
label" (represented by the NUL byte). Do not write this past the end.
Bug: 14955
Change-Id: I51e2237741807aded7ffb82c178d7d7ce5123f78
Fixes: v2.9.0rc0-1142-g53e04b621c ("DNS: fix in expand_dns_name")
Reviewed-on: https://code.wireshark.org/review/28657
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot
Reviewed-by: Erika Szelleová <szelleerika@gmail.com>
Reviewed-by: Peter Wu <peter@lekensteyn.nl>