pidgin/pidgin

Remove purple_callback_set_zero.

2020-10-07, Elliott Sales de Andrade
5f512eb3857f
Remove purple_callback_set_zero.

There's only one use now that PurplePluginInfo->ui_data is gone.

Testing Done:
Compile.

Reviewed at https://reviews.imfreedom.org/r/148/
syntax: glob
.*.swp
.DS_Store
.flatpak-builder
*.pyc
*~
\#*\#
subprojects/*/
syntax: regexp
^build(.+)?\/
win32-install-dir(\.release)?