libinput: expand PACKAGECONFIG

libinput: expand PACKAGECONFIG

The 1.30 release added support for Lua plugins, so add a
disabled-by-default PACKAGECONFIG for the Lua plugin support.

Move mtdev from being always on to an enabled-by-default PACKAGECONFIG.

Merge the udevdir evaluation directly into EXTRA_OEMESON, there's no
need for it to be a separate variable.

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>