Remove useless dependencies

[jasp00]

Some objects depend on a library without using any of its symbols; this generates a useless dependency in packaged software. RemoteZynAddSubFx depended on libdl, libX11 and libXext. The vocoder LADSPA plugin depended on libfftw3f.

[tresf]

Good catch! We can merge this, but it also needs to make it to https://github.com/swh/ladspa. Many projects use Steve's upstream swh LADSPA packages and Steve's pretty good about merging in these types of PRs.

Edit: Upstream doesn't use vocoder yet and it doesn't utilize CMakeLists.txt, so this is ours only. 👍

[jasp00]

Builds are fixed.
Should I help bringing the vocoder into SWH?

[tresf]

@jasp00 sure if you think you can help. I ran out of time working on it, but the build/xml file I was working on is available here if you think it helps: https://github.com/tresf/ladspa/blob/vocoder/vocoder_1337.xml

P.S. Sorry for delay on merging these. The work you're doing is great and we desperately need the help, we're just very behind on things currently.

Off-topic to this particular PR but the cmake stuff specifically we don't have a bunch of people great at. (I'm pretty comfortable with writing cmake, but not as much with the linking and building portions as I'm not a C++ developer)

Anyway, we'll get to your PRs ASAP. Thanks again. 👍

[tresf]

👍

[midi-pascal]

@jasp00 @tresf The commit 60740fb breaks the build on my Ubuntu 14.04 x64 with this error:
[ 78%] Generating moc_ZynAddSubFx.cxx
Generating embedded_resources.h
Linking CXX executable ../RemoteZynAddSubFx
Scanning dependencies of target zynaddsubfx
[100%] Built target lmmsobjs
[100%] [100%] Building CXX object plugins/zynaddsubfx/CMakeFiles/zynaddsubfx.dir/ZynAddSubFx.cpp.o
Scanning dependencies of target lmms
Building CXX object plugins/zynaddsubfx/CMakeFiles/zynaddsubfx.dir/moc_ZynAddSubFx.cxx.o
/usr/bin/ld: /usr/lib/x86_64-linux-gnu/libfltk.a(Fl_Double_Window.o): undefined reference to symbol 'XdbeAllocateBackBufferName'
//usr/lib/x86_64-linux-gnu/libXext.so.6: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
make[2]: *** [plugins/RemoteZynAddSubFx] Error 1
make[1]: *** [plugins/zynaddsubfx/CMakeFiles/RemoteZynAddSubFx.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
[100%] Building CXX object src/CMakeFiles/lmms.dir/lmms_automoc.cpp.o
Building CXX object src/CMakeFiles/lmms.dir/core/main.cpp.o
Linking CXX executable ../lmms
[100%] Built target lmms
Linking CXX shared module ../libzynaddsubfx.so
[100%] Built target zynaddsubfx
make: *** [all] Error 2

[jasp00]

/usr/bin/ld: /usr/lib/x86_64-linux-gnu/libfltk.a(Fl_Double_Window.o): undefined reference to symbol 'XdbeAllocateBackBufferName'

Your build is using the static library libfltk.a rather than the shared one libfltk.so. I see that the package in Ubuntu does not depend on libfltk1.3 (http://packages.ubuntu.com/trusty/lmms); this does not happen since wily.
What is the output of this command: fltk-config --use-images --ldflags ?

[midi-pascal]

@jasp00
fltk-config --use-images --ldflags
-Wl,-Bsymbolic-functions -lfltk_images -lfltk -lX11

[midi-pascal]

@jasp00 Your fix solves the problem 👍