capture_opts_add_iface_opt(), when called in a program acting as a
capture child, will fetch the description for the interface, and will
also generate a "display name" for the interface.
In the process, we clean up capture_opts_add_iface_opt() a bit,
combining duplicate code.
We rename console_display_name to just display_name, as it may also be
used in the title bar of Wireshark when capturing.
Change-Id: Ifd18955bb3cb41df4c0ed4362d4854068c825b96
Reviewed-on: https://code.wireshark.org/review/29117
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot
Reviewed-by: Guy Harris <guy@alum.mit.edu>