bump radiolib to 7.7.1

[weebl2000]

It includes some nice fixes. Full release notes here

Build here: https://mcimages.weebl.me?commitId=radiolib-7.7.1

Changed the init calls to use config instead, this prepares us for radiolib 8.0.0 removal of the now deprecated init methods.

[liamcottle]

Hey, just FYI, haven't read your code changes yet;

We are currently waiting for v7.7.2+ of RadioLib to be released, so we can merge in PR #2839

This PR might clash with an incoming PR from @oltaco which I believe bumps the repo to the latest git commit hash instead of a release version. Tagging him for awareness.

[weebl2000]

Apart from the version bump the code is functionally the same, just using the newer patterns that radiolib will switch to starting version 8.