net-analyzer/arpwatch: new revision to fix the upgrade path.

net-analyzer/arpwatch: new revision to fix the upgrade path.

All revisions before -r10 install /var/lib/arpwatch with the wrong
ownership. The -r10 revision fixes that for new installs, but doesn't
modify ${ROOT}/var/lib/arpwatch for upgraders. This new -r11 adds a
pkg_postinst function to correct the issue for upgraders.

The revision also changes one "dodir" back to "keepdir", fixing a
mistake that I made in -r10.

Closes: https://bugs.gentoo.org/554222
Package-Manager: Portage-2.3.13, Repoman-2.3.3