Some minor changes.
 * Move GCC-XML version information into VERSION and parse that from the
   top level CMakeLists.txt.

 * Edit opt-include.awk to use CMake style variables instead of
   autotools.

 * Copy gstdint.h from GCC's libgcc into gcc directory.

 * Fix localedir.h.in to set LOCALEDIR to system locale dir, rather
   than the locale dir of the install prefix.

 * Move -rdynamic flag into ${PLUGIN_FLAGS}, from ${PLUGIN_LIBRARIES}_

 * Add wrapper directory to sysroot chain, in incpath.c

 * Don't include libgcc directory in libdecnumber/CMakeLists.txt
   (libgcc is not included with gccxml)