Use bundled jack if missing

Closes #4094

cmake/linux/package_linux.sh.in

@@ -181,12 +181,10 @@ rm -f "${APPDIR}/usr/lib/libwine.so.1"
 # Use system-provided carla
 rm -f "${APPDIR}usr/lib/"libcarla*.so
 
-# Remove problematic jack library, replace with weakjack
+# Move jack out of LD_LIBRARY_PATH
 if [ -e "${APPDIR}/usr/lib/libjack.so.0" ]; then
-   rm -f "${APPDIR}/usr/lib/libjack.so.0"
    mkdir -p "${APPDIR}usr/lib/lmms/optional/"
-   cp "@CMAKE_BINARY_DIR@/optional/weakjack.so" "${APPDIR}usr/lib/lmms/optional/weakjack.so"
-   ln -sr "${APPDIR}usr/lib/lmms/optional/weakjack.so" "${APPDIR}usr/lib/lmms/optional/libjack.so.0"
+   mv "${APPDIR}/usr/lib/libjack.so.0" "${APPDIR}usr/lib/lmms/optional/"
 fi
 
 # Create AppImage

src/core/CMakeLists.txt

@@ -1,14 +1,5 @@
 IF(LMMS_HAVE_WEAKJACK)
 	set(WEAKJACK core/audio/AudioWeakJack.c)
-
-	# Build libjack.so.0 stub as weakjack.so for AppImages
-	IF(LMMS_BUILD_LINUX)
-		ADD_LIBRARY(weakjack MODULE ../../src/core/audio/AudioWeakJack.c)
-		INCLUDE_DIRECTORIES("${CMAKE_SOURCE_DIR}/include")
-		# We can't predict an AppImage build, so stash the build artifact for later
-		INSTALL(TARGETS weakjack LIBRARY DESTINATION "${CMAKE_BINARY_DIR}/optional")
-		SET_TARGET_PROPERTIES(weakjack PROPERTIES PREFIX "" SUFFIX ".so")
-	ENDIF()
 ENDIF()
 	
 set(LMMS_SRCS