Create output directory for Message Compiler tool.

Presumably, windmc.exe from MinGW-w64 fails if the output directory
doesn't exist. So create it prior to running the tool.

Additionally, removed explicit markup of the tool outputs as generated
sources. This should be done automatically by add_custom_command.

Also, added the max CMake version to silence its warnings.

CMakeLists.txt

@@ -1,9 +1,9 @@
-# Copyright 2021-2023 Andrey Semashev
+# Copyright 2021-2024 Andrey Semashev
 #
 # Distributed under the Boost Software License, Version 1.0.
 # See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt
 
-cmake_minimum_required(VERSION 3.5)
+cmake_minimum_required(VERSION 3.5...3.16)
 project(BoostLog VERSION "${BOOST_SUPERPROJECT_VERSION}" LANGUAGES CXX)
 
 include(CheckCXXSourceCompiles)
@@ -258,8 +258,8 @@ if (WIN32)
                 OUTPUT
                     "${CMAKE_CURRENT_BINARY_DIR}/src/windows/simple_event_log.h"
                     "${CMAKE_CURRENT_BINARY_DIR}/src/windows/simple_event_log.rc"
+                COMMAND "${CMAKE_COMMAND}" -E make_directory "${CMAKE_CURRENT_BINARY_DIR}/src/windows"
                 COMMAND "${CMAKE_MC_COMPILER}"
-                ARGS
                     -h "${CMAKE_CURRENT_BINARY_DIR}/src/windows"
                     -r "${CMAKE_CURRENT_BINARY_DIR}/src/windows"
                     "${CMAKE_CURRENT_SOURCE_DIR}/src/windows/simple_event_log.mc"
@@ -269,8 +269,6 @@ if (WIN32)
                     "Building src/windows/simple_event_log.mc"
                 VERBATIM
             )
-            set_source_files_properties("${CMAKE_CURRENT_BINARY_DIR}/src/windows/simple_event_log.h" PROPERTIES GENERATED TRUE)
-            set_source_files_properties("${CMAKE_CURRENT_BINARY_DIR}/src/windows/simple_event_log.rc" PROPERTIES GENERATED TRUE)
 
             if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
                 # Workaround for a windres.exe issue on MinGW-w64: by default, it uses popen to pipe preprocessed

test/test_cmake/CMakeLists.txt

@@ -6,7 +6,7 @@
 # NOTE: This does NOT run the unit tests for Boost.Log.
 #       It only tests if the CMakeLists.txt file in its root works as expected
 
-cmake_minimum_required(VERSION 3.5)
+cmake_minimum_required(VERSION 3.5...3.16)
 
 project(BoostLogCMakeSelfTest)