One can find such info in text file /usr/ports/UPDATING
make -C /usr/ports/ search name="libEGL"
and you will get the confirmation
So first remove the old package with pkg delete -f libEGL
and install mesa-libs make -C /usr/ports/graphics/mesa-libs reinstall clean
Check if there is no other missing dependencies with
pkg check -d
Either this command will show some missing dependencies, either when a given dependency is hardly updated, sometimes it is necessary to relink ports which depends on this dependency showing a broken link through this command.
Some administrators will say that one should always rebuild such port on a dependency update, but they can do that, they have powerful server. They can automate the process and make run that at delayed date.