arpwatch 2.1a15: Run do_install under fakeroot because the Makefile

arpwatch 2.1a15: Run do_install under fakeroot because the Makefile
attempts to set the ownership of the installed files (install
-o/-g):
| NOTE: make install DESTDIR=/home/lenehan/devel/oe/build/titan-glibc-25/tmp/work/arpwatch-2.1a15-r1/image
| /usr/bin/install -c -m 555 -o bin -g bin arpwatch /home/lenehan/devel/oe/build/titan-glibc-25/tmp/work/arpwatch-2.1a15-r1/image/usr/sbin
| /usr/bin/install: cannot change ownership of /home/lenehan/devel/oe/build/titan-glibc-25/tmp/work/arpwatch-2.1a15-r1/image/usr/sbin/arpwatch': Operation not permitted
| make: *** [install] Error 1
| FATAL: oe_runmake failed
This worked on my old build host running Fedora Core 4 because the -g
and -o options are ignored there when install is run by a normal
user. The above error is on a ubunutu 6.10 host which obviously
doesn't ignore those options.