WiX: Fix single-arch packaging for static experimental SDK

[speednoisemovement]

This fixes the packaging step for builds like -WindowsSDKArchitectures "Arm64"

• When choosing runtime roots, use ProductArchitecture, not sys.BUILDARCH. sys.BUILDARCH derives from Platform, which is always x86.
• Updates rotated conditions

[compnerd]

Build FAILED.

       "C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\bundle\installer.wixproj" (default target) (1:7) ->
       "C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\platforms\windows\windows.wixproj" (default target) (7:5) ->
       "C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\rtl\static\msm\rtl.static.msm.wixproj" (default target) (14:5) ->
       (CoreCompile target) -> 
         C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\rtl\static\msm\rtl.static.msm.wxs(17): error WIX0150: Undefined preprocessor variable '$(ModuleID)'. [C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\rtl\static\msm\rtl.static.msm.wixproj]
         C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\rtl\static\msm\rtl.static.msm.wxs(18): error WIX0150: Undefined preprocessor variable '$(RuntimeDirectoryComponentGuidGenerationSeed)'. [C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\rtl\static\msm\rtl.static.msm.wixproj]
         C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\rtl\static\msm\rtl.static.msm.wxs(20): error WIX0150: Undefined preprocessor variable '$(RuntimeRoot)'. [C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\rtl\static\msm\rtl.static.msm.wixproj]
         C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\rtl\static\msm\rtl.static.msm.wxs(24): error WIX0150: Undefined preprocessor variable '$(RuntimeRoot)'. [C:\Users\swift-ci\jenkins\workspace\swift-PR-build-toolchain-windows\swift-installer-scripts\platforms\Windows\rtl\static\msm\rtl.static.msm.wixproj]

    0 Warning(s)
    4 Error(s)

[compnerd]

Built at https://ci-external.swift.org/job/swift-PR-build-toolchain-windows/6147/artifact/build/artifacts/