Merge pull request swiftlang#84346 from swiftlang/jepa-main4

[build-windows-toolchain.bat] Fix a few issues with swiftlang#84326

Author: bnbarham

utils/build-windows-toolchain.bat

@@ -23,6 +23,7 @@ echo set SKIP_PACKAGING=%SKIP_PACKAGING%>> %TEMP%\call-build.cmd
 echo set SKIP_UPDATE_CHECKOUT=%SKIP_UPDATE_CHECKOUT%>> %TEMP%\call-build.cmd
 echo set REPO_SCHEME=%REPO_SCHEME%>> %TEMP%\call-build.cmd
 echo set WINDOWS_SDKS=%WINDOWS_SDKS%>> %TEMP%\call-build.cmd
+echo set HOST_ARCH_NAME=%HOST_ARCH_NAME%>> %TEMP%\call-build.cmd
 echo "%~f0">> %TEMP%\call-build.cmd
 start /i /b /wait cmd.exe /env=default /c "%TEMP%\call-build.cmd"
 set ec=%errorlevel%
@@ -81,7 +82,7 @@ call :CloneRepositories || (exit /b 1)
 
 :: We only have write access to BuildRoot, so use that as the image root.
 powershell.exe -ExecutionPolicy RemoteSigned -File %~dp0build.ps1 ^
-  %HostArchName% ^
+  %HostArchNameArg% ^
   -SourceCache %SourceRoot% ^
   -BinaryCache %BuildRoot% ^
   -ImageRoot %BuildRoot% ^