Add definitions for LIBINPUT_LED_COMPOSE and LIBINPUT_LED_KANA to support all USB HID LEDs

This adds support for Kana and Compose LEDs.

See libinput/libinput!990 (merged) for more info.

Libinput has these definitions since 1.26, hope my meson.build bump was the only thing needed for that.

Thanks to @wismill who pointed out that this is necessary in an associated xkbcommon PR

---

I've also fixed the mixed whitespace+TABs in the edited lines for consistent rendering as it otherwise broke looking like this in my editor: