- Use OPTIONS_SINGLE

PR:		ports/176257
Submitted by:	Jed Clear <jclear at speakeasy.net>
Reviewed by:	jgh

security/knock/Makefile

@@ -21,8 +21,8 @@ GNU_CONFIGURE=	yes
 
 CFLAGS+=	-I${LOCALBASE}/include
 
-OPTIONS_DEFINE=	CLIENT SERVER
-OPTIONS_DEFAULT=	CLIENT SERVER
+OPTIONS_SINGLE=	SG1
+OPTIONS_SINGLE_SG1=	CLIENT SERVER
 
 .include <bsd.port.options.mk>
 
@@ -41,11 +41,6 @@ MAN1+=		knock.1
 PLIST_FILES+=	bin/knock
 .endif
 
-pre-configure:
-.if ${PORT_OPTIONS:MSERVER} && ${PORT_OPTIONS:MCLIENT}
-IGNORE=		at least one component must be selected for installation
-.endif
-
 post-patch:
 	@${REINPLACE_CMD} -e "s#%%PREFIX%%#${PREFIX}#g"	\
 			  -e "s#eth0#fxp0#g"		\