Set protobuf_MODULE_COMPATIBLE before any find_package call

CMakeLists.txt

@@ -38,6 +38,12 @@ endif()
 # Search for project-specific dependencies
 #============================================================================
 
+# This option is needed to use the PROTOBUF_GENERATE_CPP
+# in case protobuf is found with the CMake config files
+# It needs to be set before any find_package(...) call 
+# as protobuf could be find transitively by any dependency
+set(protobuf_MODULE_COMPATIBLE TRUE)
+
 ign_find_package(sdformat11 REQUIRED VERSION 11.2.1)
 set(SDF_VER ${sdformat11_VERSION_MAJOR})
 
@@ -136,8 +142,6 @@ set(IGN_UTILS_VER ${ignition-utils1_VERSION_MAJOR})
 
 #--------------------------------------
 # Find protobuf
-# Module is needed to use the PROTOBUF_GENERATE_CPP
-set(protobuf_MODULE_COMPATIBLE TRUE)
 set(REQ_PROTOBUF_VER 3)
 ign_find_package(IgnProtobuf
                  VERSION ${REQ_PROTOBUF_VER}