[PATCH][AArch64]Fix the Cygwin build failure caused by questionable enum values in AArch64BaseInfo.h

[Tim Northover]

> But I don't how to merge code to branch 3.4.
> The log of branch3.4 is like:
>        r1 | void |
>
>        Merging r0:
>         ------------------------------
>        r0 | userID | ...

I think you're looking at the wrong branch, but i've no idea exactly
how. This is the branch we should be merging to (using svn merge, by
the looks of it):
http://llvm.org/viewvc/llvm-project/llvm/branches/release_34/

It appears Bill tried to apply your patch already, but it broke
something (http://llvm.org/viewvc/llvm-project?view=revision&revision=195429).
You probably need to work out just what before trying again.

Cheers.

Tim.