x11/nvidia-secondary-driver[-390]: Remove dead port

The requisite nvidia-hybrid-graphics port was removed in
9b8dd11af61165b9e0291140d0f8890651a6def5

libglvnd should make the need to manually move libraries around
unnecessary and has been mandatory for a long time since
5343f55d875779eca78236446cd19d67f58c4bce

Reviewed by: Tomoaki AOKI <junchoon@dec.sakura.ne.jp>
Differential Revision: https://reviews.freebsd.org/D49992