add support for mutter 49 / libmutter-17

[decathorpe]

With mutter 49, the library name has changed to libmutter-17. This is a prerequisite to building gala on Fedora 43+.

Apparently there will still be API / ABI changes between mutter 49.alpha and 49.rc, so I'm not sure if it's even a good idea to work on this yet ...

Depends on: elementary/gala#2475