Qt4Macros: Port to use message(DEPRECATION)

Modules/Qt4Macros.cmake

@@ -355,15 +355,7 @@ endmacro()
 
 macro(QT4_AUTOMOC)
   if(NOT CMAKE_MINIMUM_REQUIRED_VERSION VERSION_LESS 2.8.11)
-    if(CMAKE_WARN_DEPRECATED)
-      set(messageType WARNING)
-    endif()
-    if(CMAKE_ERROR_DEPRECATED)
-      set(messageType FATAL_ERROR)
-    endif()
-    if(messageType)
-      message(${messageType} "The qt4_automoc macro is obsolete. Use the CMAKE_AUTOMOC feature instead.")
-    endif()
+    message(DEPRECATION "The qt4_automoc macro is obsolete. Use the CMAKE_AUTOMOC feature instead.")
   endif()
   QT4_GET_MOC_FLAGS(_moc_INCS)
 
@@ -476,15 +468,7 @@ endmacro()
 
 function(qt4_use_modules _target _link_type)
   if(NOT CMAKE_MINIMUM_REQUIRED_VERSION VERSION_LESS 2.8.11)
-    if(CMAKE_WARN_DEPRECATED)
-      set(messageType WARNING)
-    endif()
-    if(CMAKE_ERROR_DEPRECATED)
-      set(messageType FATAL_ERROR)
-    endif()
-    if(messageType)
-      message(${messageType} "The qt4_use_modules function is obsolete. Use target_link_libraries with IMPORTED targets instead.")
-    endif()
+    message(DEPRECATION "The qt4_use_modules function is obsolete. Use target_link_libraries with IMPORTED targets instead.")
   endif()
   if ("${_link_type}" STREQUAL "LINK_PUBLIC" OR "${_link_type}" STREQUAL "LINK_PRIVATE")
     set(modules ${ARGN})

Tests/RunCMake/ObsoleteQtMacros/AutomocMacro-WARN-stderr.txt

-CMake Warning at .*/Modules/Qt4Macros.cmake:[^ ]+ \(message\):
+CMake Deprecation Warning at .*/Modules/Qt4Macros.cmake:[^ ]+ \(message\):
   The qt4_automoc macro is obsolete.  Use the CMAKE_AUTOMOC feature instead.
 Call Stack \(most recent call first\):
   AutomocMacro-WARN.cmake:7 \(qt4_automoc\)

Tests/RunCMake/ObsoleteQtMacros/UseModulesMacro-WARN-stderr.txt

-CMake Warning at .*/Modules/Qt4Macros.cmake:[^ ]+ \(message\):
+CMake Deprecation Warning at .*/Modules/Qt4Macros.cmake:[^ ]+ \(message\):
   The qt4_use_modules function is obsolete.  Use target_link_libraries with
   IMPORTED targets instead.
 Call Stack \(most recent call first\):