a. The BSD version will be built and installed unless
WITHOUT_BSD_CPIO is defined.
b. The GNU version will not be built or installed unless
WITH_GNU_CPIO is defined. If this is defined, the symlink
in /usr/bin will be to the GNU version whether the BSD
version is present or not.
When these changes are MFCed the defaults should be flipped.
2. Add a knob to disable the building of GNU grep. This will
make it easier for those that want to test the BSD version in
the ports.
Approved by: kientzle [1]
