CMakeLists: fix CMake warning for INCLUDE macro

CMakeLists: fix CMake warning for INCLUDE macro

Fix CMake warning for INCLUDE macro by moving the INCLUDE after the
PROJECT declaration.

CMake Warning (dev) at /usr/share/cmake-3.31/Modules/GNUInstallDirs.cmake:253 (message):
  Unable to determine default CMAKE_INSTALL_LIBDIR directory because no
  target architecture is known.  Please enable at least one language before
  including GNUInstallDirs.

Signed-off-by: David Härdeman <[email protected]>
[ improve commit description ]
Link: https://github.com/openwrt/uci/pull/7
Signed-off-by: Christian Marangi <[email protected]>