Fix FELIG build after recent merge

Hi Frans,

This is the merge request for FLX-1953. @riluz implemented lpGBT for FELIG in FLX-1428, but I noticed that the FELIG firmware could not be built directly from phase2/master. The phase2/master branch provides newer versions of some entities that FELIG uses, and the old instantiations present in FELIG do not work with these newer versions.

This MR fixes these issues, and we can now build a functional FELIG lpGBT bitfile directly from phase2/master.

I am not entirely sure about commit 2266951f, though. I had to edit the emcclk constraint in felix_top_BNL712.xdc to use a vector instead of a single net, and I'm not totally clear on why this ended up being necessary. This is the only change that would affect anything outside of FELIG.