* Change some functions to use `ZSubscription_t`
* Cleanup redundant `zephyr_triple` allocations
* Inline `zephyr_subscribe_failed`
* Replace `find_sub_by_sub` and `find_sub_by_id` with `g_slist_find_custom`
* Rename functions related to `zephyr_triple`
Testing Done:
Compile.
Reviewed at https://reviews.imfreedom.org/r/450/
/*
* Purple buddy notification plugin.
*
* Copyright (C) 2000-2001, Eric Warmenhoven (original code)