[clang] [flang] [flang] Enable alias tags pass by default (PR #73111)

[Slava Zakharin via cfe-commits]

https://github.com/vzakhari commented:

Thank you for the changes, Tom!

I have one minor comment, but I would like to ask to merge this after US holidays, if possible.  Could you please postpone the merging until Monday GMT?

https://github.com/llvm/llvm-project/pull/73111