use VERSION_GREATER instead of GREATER to compare the protobuf version

Author: Firenox89

CMakeLists.txt

@@ -94,7 +94,7 @@ endif()
 
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DEGL_NO_X11")
 
-if((Protobuf_VERSION GREATER "3.7") OR (Protobuf_VERSION EQUAL "3.7"))
+if((Protobuf_VERSION VERSION_GREATER "3.7") OR (Protobuf_VERSION VERSION_EQUAL "3.7"))
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DUSE_PROTOBUF_CALLBACK_HEADER")
 endif()