audio/libgpod: remove wrong dependency on gtk20

This port actually only depends on gdkpixbuf2
While here remove the mono slave ports which is not depended on anymore

MOVED

@@ -17763,3 +17763,4 @@ www/webtrees||2023-01-30|Has expired: Uses obsolete PHP version; use www/webtree
 x11-toolkits/libsexy||2023-01-30|Depends on EOLed gtk+20, not depended on in the ports tree
 x11-toolkits/gtkmathview||2023-01-30|Depends on EOLed gtk+20, not depended on in the ports tree
 x11-toolkits/vdk||2023-01-30|Depends on EOLed gtk+20, not depended on in the ports tree
+audio/libgpod-sharp||2023-02-01|Depends on EOLed gtk+20, not depended on in the ports tree

audio/Makefile

@@ -376,7 +376,6 @@
     SUBDIR += libgig
     SUBDIR += libgme
     SUBDIR += libgpod
-    SUBDIR += libgpod-sharp
     SUBDIR += libgroove
     SUBDIR += libid3tag
     SUBDIR += libinstpatch

audio/libgpod/Makefile

@@ -21,23 +21,19 @@ CONFIGURE_ARGS=	--disable-udev --without-hal \
 		--without-python \
 		--with-html-dir="${DOCSDIR:H}"
 USE_CSTD=	gnu89
-USE_GNOME=	gdkpixbuf2 gtk20 intltool libxml2
+USE_GNOME=	gdkpixbuf2 intltool libxml2
 INSTALL_TARGET=	install-strip
 USE_LDCONFIG=	yes
 
-OPTIONS_DEFINE=	DOCS IMOBILE MONO
+OPTIONS_DEFINE=	DOCS IMOBILE
 OPTIONS_DEFAULT=IMOBILE
-OPTIONS_EXCLUDE?=	MONO
 OPTIONS_SUB=	yes
 
 IMOBILE_DESC=	Apple iPhone/iPod Touch support
 
 IMOBILE_LIB_DEPENDS=	libimobiledevice-1.0.so:comms/libimobiledevice
 IMOBILE_CONFIGURE_WITH=	libimobiledevice
 
-MONO_USE=		GNOME=gtksharp20
-MONO_CONFIGURE_WITH=	mono
-
 PORTDOCS=	ChangeLog NEWS README*
 
 .include <bsd.port.options.mk>
@@ -50,16 +46,9 @@ post-patch:
 	@${REINPLACE_CMD} -e 's|libplist >= 1\.0|libplist-2.0 >= 2.0|g' \
 		${WRKSRC}/configure
 
-post-patch-MONO-on:
-	@${REINPLACE_CMD} 's/gmcs/mcs/g' ${WRKSRC}/configure ${WRKSRC}/m4/mono.m4
-
-.if ${SLAVE_PORT} == no
 post-install:
 	${INSTALL_PROGRAM} ${WRKSRC}/tools/ipod-time-sync \
 		${STAGEDIR}${PREFIX}/bin
-.endif
-
-post-install-MONO-off:
 	@${RM} ${STAGEDIR}${PREFIX}/libdata/pkgconfig/libgpod-sharp.pc
 
 post-install-DOCS-on: