Building the Xvnc server requires libtool control files of rdr, rfb,

Building the Xvnc server requires libtool control files of rdr, rfb,
network and Xregion, which a cmake build will NOT produce, this macro
tries to create a libtool control file *.la for the specified target
with libdependencies for a static library target.

Due to the automake part of Xvnc references to libtool files in source
tree you need to build vncviewer using cmake in the source tree.

git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4482 3789f03b-4d11-0410-bbf8-ca57d06f2519