net-misc/asterisk: version bump to 16.9.0

net-misc/asterisk: version bump to 16.9.0

Minor changes to accomodate upstream.  Primarily:

1.  Explicitly do not use bundled pjsip / janson.
2.  Depend on libedit explicitly (it's no longer bundled at all).
3.  Allow for SRV/NAPTR processing via libunbound.
4.  Asterisk 16 requires pjsip 2.9.
5.  Depend on dev-libs/jansson-2.11

Eliminate use of MY_P (very, very old versions of asterisk used _ in
name apparently, this is no longer the case so just use P instead).

Closes: https://bugs.gentoo.org/597082
Package-Manager: Portage-2.3.89, Repoman-2.3.20
Signed-off-by: Jaco Kroon <jaco@uls.co.za>
Signed-off-by: Joonas Niilola <juippis@gentoo.org>