The existence of the log global was in part due to early (pre-merge)
versions of the Lua plugins supporting multiple libinput plugin objects
per file. This is no longer the case and integrating the log functions
into the (single) libinput object makes the code more obvious (we're
calling libinput:log_debug() now, so it's obviously a libinput log
function) and we no longer mix dot with colon notations.
Part-of: <https://gitlab.freedesktop.org/libinput/libinput/-/merge_requests/1350>
Because our lua hooks don't expose the device-added callback we need to
cache any calls to disable a feature and then apply it quietly when the
device is actually added. Any other call can go straight through.
Part-of: <https://gitlab.freedesktop.org/libinput/libinput/-/merge_requests/1249>
