tigervnc: Build inside source directory

[Work around a build failure.][1]

    [BEE] make -j100 TIGERVNC_SRCDIR=/dev/shm/bee-root/tigervnc/tigervnc-1.9.0-0/source
    [BEE] […]
    [BEE] make[2]: Entering directory '/dev/shm/bee-root/tigervnc/tigervnc-1.9.0-0/build/unix/xserver/hw/vnc'
    [BEE]   CC       libvnc_la-vncModule.lo
    [BEE]   CC       libvnccommon_la-vncExt.lo
    [BEE]   CXX      libvnccommon_la-vncExtInit.lo
    [BEE]   CC       libvnccommon_la-vncSelection.lo
    [BEE]   CC       libvnccommon_la-vncHooks.lo
    [BEE] make[2]: *** No rule to make target '/dev/shm/bee-root/tigervnc/tigervnc-1.9.0-0/source/common/network/libnetwork.la', needed by 'libvnc.la'.  Stop.

[1]: https://github.com/TigerVNC/tigervnc/issues/742

tigervnc.be0

@@ -32,7 +32,7 @@ PATCHURL+=(/src/mariux/patches/tigervnc-vncserver-Change-default-xstartup-to-xfc
 ## outside the source directory and needs to be built inside the source
 ## directory.
 
-# build_in_sourcedir
+build_in_sourcedir
 
 ###############################################################################
 ## bee cannot detect buildtypes specified in subdirectories.
@@ -69,7 +69,6 @@ mee_configure() {
         fi
         eval DEFCONFIG=\"${DEFCONFIG}\"
 
-        start_cmd cp -R $S/unix/xserver $B/unix/
         start_cmd cp -R $S/xorg-server-$XORG_SERVER_VERSION/* $B/unix/xserver/
         start_cmd cd unix/xserver
         start_cmd patch -p1 < $S/unix/xserver$XORG_SERVER_NNN.patch