Update module comment in GHC.Internal.TH.Lib

@sgraf812 writes:

I think [the module comment on GHC.Internal.TH.Lib] is out of date. The reason we separate is that these identifiers are builtin. Honestly, I don't really know why we separate Language.Haskell.TH.Lib from ...TH

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information