mtr: Add PKG_LICENSE information

Signed-off-by: Jonathan McCrohan <jmccrohan@gmail.com>
sslh: Add PKG_LICENSE information

Signed-off-by: Jonathan McCrohan <jmccrohan@gmail.com>
wavemon: Add PKG_LICENSE information

Signed-off-by: Jonathan McCrohan <jmccrohan@gmail.com>
xinetd: Add PKG_LICENSE information

Signed-off-by: Jonathan McCrohan <jmccrohan@gmail.com>
muninlite: Fix PKG_LICENSE information

muninlite is GPL-2.0+, not GPL-2.0 exclusively

Signed-off-by: Jonathan McCrohan <jmccrohan@gmail.com>