Dealing with compile options that need parameters

[Francisco J. Tsao Santín <tsao%disroot.org@localhost>]

Following with my attempt to package openfortivpn, I try to add some
extra build options using bsd.options.mk.
I could apply what I learned in the documentation[0] in some cases
without a problem, but I have doubts with an option like this:
--with-ppp=[PATH]

I put in my options.mk that lines:
...
.if !empty(PKG_OPTIONS:Mopenfortivpn-ppp)
CONFIGURE_ARGS+=	--with-ppp=${PPP_PATH:Q}
.endif
...
I tested adding to my mk.conf.local:
...
PKG_OPTIONS.openfortivpn+= openvfortivpn-ppp
PPP_PATH=/usr/sbin/pppd
...
And it runs fine. But of course pkglint warns me:
...
WARN: options.mk:10: Undocumented option "openfortivpn-ppp".
...
WARN: options.mk:49: PPP_PATH is used but not defined.
...

The first warning, of course, raised because I don't have an entry at
mk/defaults/options.description. But about PPP_PATH I don't know if I
can ignore the warning, and simply document that variable (must be added
to mk/defaults/mk.conf??).

[0]https://www.netbsd.org/docs/pkgsrc/options.html
-- 
Francisco J. Tsao Santín
http://gattaca.es
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