lib/ofed: Move to the rdma package

We have an existing rdma package for IB/rdma-related files, but most
of ofed isn't in that package, making it rather useless. Move all of
lib/ofed to the rdma package.

Add a separate rdma-lib package using LIB_PACKAGE, since utilities
depends on the rdma libraries and we don't want that to pull in all
of rdma.

This change moves files between packages so, until we have a proper
policy on how to handle this in release/stable branches, it should
not be MFC'd.

PR: 263227
MFC after: never
Reviewed by: manu
Sponsored by: https://www.patreon.com/bsdivy
Differential Revision: https://reviews.freebsd.org/D53604