Add support SWIG 4.1.0, drop support for < 4.0.1

https://bugs.gentoo.org/878587

CMakeLists.txt

@@ -173,7 +173,7 @@ if(WANT_PYTHON AND NOT EXISTS
 	endif()
 endif()
 if(search_swig)
-	find_package(SWIG 3.0.0)
+	find_package(SWIG 4.0.1)
 	if(NOT SWIG_FOUND)
 		message(FATAL_ERROR
 			"Can't find SWIG, therefore Perl and Python aren't supported. "

modules/modperl/CMakeLists.txt

@@ -53,7 +53,6 @@ if(SWIG_FOUND)
 		"-I${PROJECT_SOURCE_DIR}/include"
 		"-I${CMAKE_CURRENT_SOURCE_DIR}/.."
 		"-I${CMAKE_CURRENT_SOURCE_DIR}/include"
-		-DZNC_EXPORT_LIB_EXPORT
 		-outdir "${CMAKE_CURRENT_BINARY_DIR}"
 		-o "${CMAKE_CURRENT_BINARY_DIR}/modperl_biglib.cpp"
 		"${CMAKE_CURRENT_SOURCE_DIR}/modperl.i"

modules/modpython/CMakeLists.txt

@@ -50,7 +50,6 @@ if(SWIG_FOUND)
 		"-I${PROJECT_BINARY_DIR}/include"
 		"-I${PROJECT_SOURCE_DIR}/include"
 		"-I${CMAKE_CURRENT_SOURCE_DIR}/.."
-		-DZNC_EXPORT_LIB_EXPORT
 		-outdir "${CMAKE_CURRENT_BINARY_DIR}"
 		-o "${CMAKE_CURRENT_BINARY_DIR}/modpython_biglib.cpp"
 		"${CMAKE_CURRENT_SOURCE_DIR}/modpython.i"