Build: Use imported target `EXPAT::EXPAT` instead of variables

Source/CMakeLists.txt

@@ -743,7 +743,6 @@ target_include_directories(
     "${CMake_BINARY_DIR}/Source"
     "${CMake_SOURCE_DIR}/Source"
     "${CMake_SOURCE_DIR}/Source/LexerParser"
-    ${CMAKE_EXPAT_INCLUDES}
     ${CMAKE_TAR_INCLUDES}
     ${CMake_HAIKU_INCLUDE_DIRS}
   )
@@ -752,8 +751,8 @@ target_link_libraries(
   PUBLIC
     cmstd
     cmsys
+    EXPAT::EXPAT
     ZLIB::ZLIB
-    ${CMAKE_EXPAT_LIBRARIES}
     ${CMAKE_TAR_LIBRARIES}
     ${CMAKE_CURL_LIBRARIES}
     ${CMAKE_JSONCPP_LIBRARIES}

Source/Modules/CMakeBuildUtilities.cmake

@@ -197,6 +197,7 @@ else()
   set(CMAKE_EXPAT_INCLUDES)
   set(CMAKE_EXPAT_LIBRARIES cmexpat)
   add_subdirectory(Utilities/cmexpat)
+  add_library(EXPAT::EXPAT ALIAS cmexpat)
   CMAKE_SET_TARGET_FOLDER(cmexpat "Utilities/3rdParty")
 endif()