pidgin/pidgin

Make our windows builds usable from meson.
release-2.x.y
2021-04-19, Gary Kramlich
2ff89178eb3d
Make our windows builds usable from meson.

This creates our pkg-config files on windows as well as fixes an include in
pidgin.h which can cause some issues.

This isn't usable as is, as you need a machine-file and a pkg-config wrapper
to make this all work, but that will be updated in the win32-dev.7z file thats
on data.imfreedom.org.

Testing Done:
Compiled guifications2 (which now uses meson) on windows and verified it works.

Reviewed at https://reviews.imfreedom.org/r/615/
/** @page core-signals Core Signals
@signals
@signal quitting
@signal uri-handler
@endsignals
@see core.h
<hr>
@signaldef quitting
@signalproto
void (*quitting)();
@endsignalproto
@signaldesc
Emitted when libpurple is quitting.
@endsignaldef
@signaldef uri-handler
@signalproto
gboolean (*uri_handler)(const gchar *proto, const gchar *cmd, GHashTable *params);
@endsignalproto
@signaldesc
Emitted when handling a registered URI.
@param proto The protocol of the URI.
@param cmd The 'command' of the URI.
@param params Any key/value parameters from the URI.
@endsignaldef
*/
// vim: syntax=c.doxygen tw=75 et