state: Fix LatchMods mutation to SetMods or LockMods Previously we use inlined version of the corresponding filter functions of the `SetMods()` and `LockMods()` actions, but they were incomplete and did not set some fields (`priv`, `refcnt`) properly. Also, it is error-prone: it requires discipline to keep it in sync. E.g. before this commit, converting to `LockMods()` would always try to unlock `CapsLock` due to the wrong value of the `priv` field. Fixed by using the corresponding filter functions directly, so that we always mutate the filter properly, as in `xkb_filter_group_latch_func`.