[GHC] Batch modify: #15253, #15260, #15273, #15283, #15288, #15291, ...

[GHC]

Batch modification to #15253, #15260, #15273, #15283, #15288, #15291, #15292, #15296, #15297 by bgamari:
milestone to 8.8.1

Comment:
These won't be addressed in GHC 8.6.

-- 
Tickets URL: <http://ghc.haskell.org/trac/ghc/query?id=15253%2C15260%2C15273%2C15283%2C15288%2C15291%2C15292%2C15296%2C15297>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler