tigervnc: Add libraries from fltl-config

There is some logic in CMakeLists.txt to create the list of required
link libraries in FLTK_LIBRARIES. This depends on the output of
FindFLTK.cmake provided by cmake.

The logic seems to fail as several libraries are missing in the end:

    [ 89%] Linking CXX executable vncviewer
    /usr/lib/gcc/x86_64-pc-linux-gnu/7.3.0/../../../../x86_64-pc-linux-gnu/bin/ld:
    /usr/lib/gcc/x86_64-pc-linux-gnu/7.3.0/../../../../lib64/libfltk.a(Fl_Window_shape.o):
    undefined reference to symbol 'dlsym@@GLIBC_2.2.5'
    /lib/libdl.so.2: error adding symbols: DSO missing from command line
    collect2: error: ld returned 1 exit status
    vncviewer/CMakeFiles/vncviewer.dir/build.make:427: recipe for target
    'vncviewer/vncviewer' failed
    make[2]: *** [vncviewer/vncviewer] Error 1

Overwrite the computed FLTK_LIBRARIES with the output of

    fltk-config --use-images --ldflags

which seems to enumerate the required libraries.

tigervnc.be0

@@ -53,9 +53,9 @@ SRCURL[0]="https://github.com/TigerVNC/tigervnc/archive/v${PKGVERSION}/tigervnc-
 #    bee_patch "${@}"
 #}
 
-#mee_configure() {
-#    bee_configure
-#}
+mee_configure() {
+    bee_configure -DFLTK_LIBRARIES="$(fltk-config --use-images --ldflags)"
+}
 
 #mee_build() {
 #    bee_build