Merge pull request swiftlang#34797 from drodriguez/windows-temp-tmp-and-tmpdir

[windows] Set TMP and TEMP, as well as TMPDIR.

Author: drodriguez

utils/build-windows.bat

@@ -55,6 +55,8 @@ set install_directory=%build_root%\Library\Developer\Toolchains\unknown-Asserts-
 
 md %build_root%\tmp
 set TMPDIR=%build_root%\tmp
+set TMP=%build_root%\tmp
+set TEMP=%build_root%\tmp
 
 md %build_root%\tmp\org.llvm.clang.9999
 set CUSTOM_CLANG_MODULE_CACHE=%build_root%\tmp\org.llvm.clang.9999