cmake: Set the path for installing API documentation.

The documentation contained here is not the usual manual,
so it does not belong to the TDE user documentation.

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>

CMakeLists.txt

@@ -39,6 +39,8 @@ include( TDEMacros )
 if( CMAKE_INSTALL_LIBDIR )
   tde_setup_install_path( LIB_INSTALL_DIR "${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR}" )
 endif()
+tde_setup_install_path( HTML_INSTALL_DIR "${CMAKE_INSTALL_PREFIX}/share/doc/lib${PROJECT_NAME}/HTML" )
+
 include( TDESetupPaths )
 tde_setup_paths( )