bsd.port.mk would always find the executable (using which), even if
there wasn't an executable in the $PATH. I've modified bsd.port.mk to
look for the executable directly, and simplified the shell code
somewhat in the process. There may be a lurking bug in shell exit
status handling here.
Noted by matthew green <mrg@madrugada.eterna.com.au> and Chris
Demetriou <cgd@netbsd.org> (PR pkg/4337) but I was too stupid to
realise what was happening. That, and a copy of gmake in
/usr/local/bin.
c72a8fd6be