Move cmake.m4 from Utilities to Auxiliary

The latter fits more consistently with other third party integration
files.

Auxiliary/CMakeLists.txt

 install(FILES cmake-help.vim cmake-indent.vim cmake-syntax.vim DESTINATION ${CMAKE_DATA_DIR}/editors/vim)
 install(FILES cmake-mode.el DESTINATION ${CMAKE_DATA_DIR}/editors/emacs)
+install(FILES cmake.m4 DESTINATION share/aclocal)
 add_subdirectory (bash-completion)

Utilities/CMakeLists.txt

@@ -127,7 +127,6 @@ install(FILES
   ${DOCBOOK_FILES}
   DESTINATION ${CMAKE_DOC_DIR}
   )
-install(FILES cmake.m4 DESTINATION share/aclocal)
 
 # Drive documentation generation.
 add_custom_target(documentation ALL DEPENDS ${DOC_FILES} ${CMake_BINARY_DIR}/Docs/cmake.txt )