cmake: if not configured by user, enable c++14 for root7

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cmake/modules/RootBuildOptions.cmake

@@ -308,12 +308,12 @@ ROOT_APPLY_OPTIONS()
 if(root7)
   if(NOT CMAKE_CXX_STANDARD)
       set(CMAKE_CXX_STANDARD 14 CACHE STRING "C++14 standard used with root7")
-  endif()
-  if(NOT CMAKE_CXX_STANDARD GREATER 11)
+      message(STATUS "Enable C++14 for compilation of root7 components")
+  elseif(NOT CMAKE_CXX_STANDARD GREATER 11)
       message(FATAL_ERROR ">>> C++14 standard required with root7")
    endif()
    if(NOT webui AND NOT webui_disabled)
-      set(webui ON CACHE BOOL "(webui build automatically when root7 is enabled)" FORCE)
+      set(webui ON CACHE BOOL "(webui built automatically when root7 is enabled)" FORCE)
    endif()
 endif()