When provisioning windows machine, it seems that detecting architecture
by checking [System.Environment]::Is64BitProcess doesn't work properly.
Instead pass 32 or 64 as an argument when calling powershell script.

Change-Id: I890ad141b8ef194275848d0e656431753463cd2b
Reviewed-by: Heikki Halmet <heikki.halmet@qt.io>