Mk/bsd.port.mk: turn create-binary-wrappers into more make(1) syntax

[bapt]

Summary

Instead of looping on all files to create, actually create proper targets
for each files to be created, meaning they won't be overwritten if they
are already existing.

while here mark the parent target itself as .PHONY

[mat]

I prefer the current version, it is readable, the new is more like magic and harder to understand.
If I were pedantic I'd say it goes against lessons 1, 2, 5 and probably others of https://en.wikipedia.org/wiki/The_Elements_of_Programming_Style.