Fix TableGen subtarget-emitter to handle A9/Swift.
Fix TableGen subtarget-emitter to handle A9/Swift.

A9 uses itinerary classes, Swift uses RW lists. This tripped some
verification when we're expanding variants. I had to refine the
verification a bit.

git-svn-id: a4a6f32337ebd29ad4763b423022f00f68d1c7b7@178357 91177308-0d34-0410-b5e6-96231b3b80d8

lodyagin/bare_cxx,lodyagin/bare_cxx,lodyagin/bare_cxx,lodyagin/bare_cxx,lodyagin/bare_cxx