audio/libworkman: Deprecate and set expiration date to 2023-03-31

Abandonware, no development in 20+ years and not used anywhere in tree

audio/libworkman/Makefile

@@ -11,6 +11,9 @@ COMMENT=	Workman library required by some audio apps
 LICENSE=	LGPL20+
 LICENSE_FILE=	${WRKSRC}/COPYING.LIB
 
+DEPRECATED=	Abandonware, no development in 20+ years
+EXPIRATION_DATE=2023-03-31
+
 USES=		imake
 WRKSRC=		${WRKDIR}/libworkman
 USE_LDCONFIG=	yes