Need to install libxxf86vm-dev package for Linux build

[ghpenguin]

In Devuan Linux, source build failed at the linking stage.

[ 97%] Building C object CMakeFiles/InstantMeshes.dir/ext/rply/rply.c.o
[ 98%] Linking CXX executable "Instant Meshes"
/usr/bin/ld: cannot find -lXxf86vm
collect2: error: ld returned 1 exit status
make[2]: *** [CMakeFiles/InstantMeshes.dir/build.make:435: Instant Meshes] Error 1
make[1]: *** [CMakeFiles/Makefile2:183: CMakeFiles/InstantMeshes.dir/all] Error 2
make: *** [Makefile:149: all] Error 2

After installation libxxf86vm-dev package, it built successfully.
[ 2%] Built target bin2c
[ 15%] Built target glfw_objects
[ 42%] Built target nanogui-obj
[ 43%] Built target nanogui
[ 78%] Built target tbb_static
[ 79%] Linking CXX executable "Instant Meshes"
[ 98%] Built target InstantMeshes
Scanning dependencies of target glfw
[100%] Linking C static library libglfw3.a
[100%] Built target glfw