audio/libopenmpt: Add CPE information

Approved by:    portmgr (blanket)

audio/libopenmpt/Makefile

@@ -13,9 +13,11 @@ COMMENT=	Module music library based on OpenMPT
 LICENSE=	BSD3CLAUSE
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
-USES=		compiler:c++11-lang gmake libtool pkgconfig
+USES=		compiler:c++11-lang cpe gmake libtool pkgconfig
 USE_LDCONFIG=	yes
 
+CPE_VENDOR=	openmpt
+
 GNU_CONFIGURE=	yes
 
 CONFIGURE_ARGS+=	--without-portaudiocpp