[ports] r438901 causes PACKAGES= issues

[Harry Schmalzbauer]

 Mk&bsd.ports.mk still tells:
# PACKAGES              - A top level directory where all packages go
(rather than
#                                 going locally to each port).
#                                 Default: ${PORTSDIR}/packages

Since r438901 (
https://svnweb.freebsd.org/ports?view=revision&sortby=date&revision=438901
)
defining PACKAGES, 'make -VPKGFILE' leads to:
make[1]: "/usr/ports/Mk/bsd.port.mk" line 5118: warning: duplicate
script for target "/mnt/pkg/ivybridge/FreeBSD" ignored
make[1]: "/usr/ports/Mk/bsd.port.mk" line 3288: warning: using previous
script for "/mnt/pkg/ivybridge/FreeBSD" defined here
make: "/usr/ports/Mk/bsd.port.mk" line 5118: warning: duplicate script
for target "/mnt/pkg/ivybridge/FreeBSD" ignored
make: "/usr/ports/Mk/bsd.port.mk" line 3288: warning: using previous
script for "/mnt/pkg/ivybridge/FreeBSD" defined here
/mnt/pkg/ivybridge/FreeBSD:11:amd64/All/zxfer-1.1.6.txz

In that case, the ':' is the culprit, but I think this is a completely
legal path name and support for it should be fixed, especially
considering pkg definitions...

Thanks,

-harry