net/mediastreamer: Move to FFmpeg 4

Fails to build with FFmpeg 6

PR:		270314
Approved by:	portmgr (blanket, build fix)
Sponsored by:	Blinkinblox

net/mediastreamer/Makefile

@@ -54,7 +54,7 @@ VIDEOOPT_DESC=	Video options
 QTGL_DESC=		Qt OpenGL rendering support
 
 FFMPEG_IMPLIES=		VIDEO
-FFMPEG_LIB_DEPENDS=	libavcodec.so:multimedia/ffmpeg
+FFMPEG_LIB_DEPENDS=	libavcodec.so.58:multimedia/ffmpeg4
 FFMPEG_CMAKE_BOOL=	ENABLE_FFMPEG
 G726_LIB_DEPENDS=	libspandsp.so:comms/spandsp
 G726_CMAKE_BOOL=	ENABLE_G726
@@ -98,6 +98,8 @@ XVIDEO_LDFLAGS=		-L${LOCALBASE}/lib -lX11
 post-patch:
 	@${REINPLACE_CMD} 's,gsm/gsm\.h,gsm.h,' \
 		${WRKSRC}/cmake/FindGSM.cmake ${WRKSRC}/src/audiofilters/gsm.c
+	@${REINPLACE_CMD} -e 's|%%LOCALBASE%%|${LOCALBASE}|g' \
+		${PATCH_WRKSRC}/CMakeLists.txt
 .if ${CHOSEN_COMPILER_TYPE} == gcc
 	@${REINPLACE_CMD} '/-Wno-format-truncation/d' ${WRKSRC}/CMakeLists.txt
 .endif

net/mediastreamer/files/patch-CMakeLists.txt

@@ -0,0 +1,10 @@
+--- CMakeLists.txt.orig	2023-04-25 11:15:51 UTC
++++ CMakeLists.txt
+@@ -260,6 +260,7 @@ if(ENABLE_VIDEO)
+ 	add_definitions(-DVIDEO_ENABLED)
+ endif()
+ if(ENABLE_FFMPEG)
++	set(CMAKE_PREFIX_PATH "%%LOCALBASE%%/ffmpeg4;%%LOCALBASE%%/ffmpeg4/libexec")
+ 	find_package(FFMpeg REQUIRED)
+ else()
+ 	add_definitions(-DNO_FFMPEG)