I've just deleted the copy of netinet/if_ether.h which was
put to sys/lib/libsa when the ARP framework changed.
I removed all references as far as I found them.
However, I could not test if the code still compiles at
most architectures - there might be depencies which I
didn't see.

If there are problems which can not be solved by
"make depend", forgive me.

best regards
Matthias