net-mgmt/nrpe: Adding monplugins flavor to nrpe

Some user asked to add a flavor to permit to have nrpe already
packaged with monplugins.
This patch add this functionality and has been tested (both
flavors default and monplugins with poudriere under 13.4-RELEASE).

Sponsored by:	Klara, Inc.
Approved by:	0mp (mentor)
Approved by:	bofh (maintainer)
Differential Revision:	https://reviews.freebsd.org/D48111

net-mgmt/nrpe/Makefile

@@ -10,6 +10,10 @@ WWW=		https://www.nagios.org/
 LICENSE=	GPLv2+
 LICENSE_FILE=	${WRKSRC}/LICENSE.md
 
+FLAVORS=	default monplugins
+FLAVOR?=	${FLAVORS:[1]}
+monplugins_PKGNAMESUFFIX=	-monplugins
+
 USES=		perl5
 USE_GITHUB=	yes
 GH_ACCOUNT=	NagiosEnterprises
@@ -36,7 +40,7 @@ PLIST_SUB=	NAGIOSUSER=${NAGIOSUSER} \
 		NRPE_PIDDIR=${NRPE_PIDDIR}
 
 OPTIONS_DEFINE=	SSL ARGS
-OPTIONS_DEFAULT=NAGPLUGINS SSL
+OPTIONS_DEFAULT=SSL
 OPTIONS_RADIO=	PLUGINS
 OPTIONS_RADIO_PLUGINS=	MONPLUGINS NAGPLUGINS
 
@@ -57,6 +61,14 @@ NAGIOSGROUP?=	nagios
 
 NRPE_PIDDIR?=	/var/run/nrpe
 
+.if ${FLAVOR:U} == default
+OPTIONS_DEFAULT+=	NAGPLUGINS
+.endif
+
+.if ${FLAVOR:U} == monplugins
+OPTIONS_DEFAULT+=	MONPLUGINS
+.endif
+
 post-patch:
 	@${REINPLACE_CMD} -e 's|/var/run/nrpe.pid|${NRPE_PIDDIR}/nrpe.pid|g' \
 		-e 's|/usr/lib/nagios/plugins/|${LOCALBASE}/libexec/nagios/|g' \