net/freeswitch: change dependency from ffmpeg to ffmpeg4

PR:		270276
Reported-by:	diizzy

Author: jbeich

net/freeswitch/Makefile

@@ -207,4 +207,5 @@ post-install:
 		(cd ${WRKSRC}/conf && \
 		${COPYTREE_SHARE} . ${STAGEDIR}${EXAMPLESDIR})
 
+.include "${.CURDIR:H:H}/multimedia/ffmpeg4/override.mk"
 .include <bsd.port.mk>