Allow end-users to easily change the MaaS commissioning/deploying
timeouts by simply editing the reclass model.
While at it, use arch-specific values and bump deploy timeout on
AArch64 to 20 minutes instead of 15.
Change-Id: I37ae434ecebdd64effb007baa06c722b1db15c66 Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>