Log Message:
Update to 6.54

Upstream changes:
6.54  Sun Dec 16 11:06:07 CET 2018
        - reinstate Coro::Select::select prototype - it breaks more than it fixes.

6.53  Sun Dec 16 10:33:15 CET 2018
        - the autogenerated prototypes of Coro::AIO now add ";" at the end
          to avoid generating named unary operators and messing up parsing
          (mostly affects aio_mlockall 4 | 8 which was parsed as
          (aio_mlockall 4) | 8).
        - do not use a prototype for select in Coro::Select, as CORE::select also
          doesn't have one.