Include the local rfb headers to avoid build errors in case libvncserver is also installed in the system location.
BUG: 256642

git-svn-id: svn://anonsvn.kde.org/home/kde/trunk/KDE/kdenetwork/krfb/libvncserver@1196901 283d02a7-25f6-0310-bc7c-ecb5cbfe19da