Define void using <$ (re #9827)
Define void using <$ (re #9827)

`() <$ x` is sometimes better than `fmap (const ()) x` and should
never be worse.

Reviewed By: ekmett

Differential Revision: https://phabricator.haskell.org/D521

siddhanathan/ghc,sgillespie/ghc,acowley/ghc,gridaphobe/ghc,GaloisInc/halvm-ghc,tjakway/ghcjvm,siddhanathan/ghc,vTurbine/ghc,gridaphobe/ghc,christiaanb/ghc,vikraman/ghc,TomMD/ghc,forked-upstream-packages-for-ghcjs/ghc,forked-upstream-packages-for-ghcjs/ghc,mcschroeder/ghc,ghc-android/ghc,ezyang/ghc,mcschroeder/ghc,mcschroeder/ghc,vTurbine/ghc,mettekou/ghc,elieux/ghc,anton-dessiatov/ghc,wxwxwwxxx/ghc,nathyong/microghc-ghc,mettekou/ghc,GaloisInc/halvm-ghc,bitemyapp/ghc,snoyberg/ghc,acowley/ghc,GaloisInc/halvm-ghc,gcampax/ghc,christiaanb/ghc,forked-upstream-packages-for-ghcjs/ghc,sgillespie/ghc,wxwxwwxxx/ghc,AlexanderPankiv/ghc,anton-dessiatov/ghc,forked-upstream-packages-for-ghcjs/ghc,mfine/ghc,nushio3/ghc,vikraman/ghc,da-x/ghc,TomMD/ghc,mettekou/ghc,olsner/ghc,elieux/ghc,vikraman/ghc,TomMD/ghc,nushio3/ghc,snoyberg/ghc,gcampax/ghc,sdiehl/ghc,snoyberg/ghc,fmthoma/ghc,urbanslug/ghc,ml9951/ghc,GaloisInc/halvm-ghc,sdiehl/ghc,mettekou/ghc,nushio3/ghc,vikraman/ghc,olsner/ghc,AlexanderPankiv/ghc,mcschroeder/ghc,tjakway/ghcjvm,christiaanb/ghc,sdiehl/ghc,ezyang/ghc,fmthoma/ghc,ghc-android/ghc,TomMD/ghc,sgillespie/ghc,elieux/ghc,shlevy/ghc,sdiehl/ghc,nathyong/microghc-ghc,ml9951/ghc,gcampax/ghc,bitemyapp/ghc,green-haskell/ghc,AlexanderPankiv/ghc,christiaanb/ghc,christiaanb/ghc,forked-upstream-packages-for-ghcjs/ghc,gcampax/ghc,ezyang/ghc,olsner/ghc,nkaretnikov/ghc,ml9951/ghc,mcschroeder/ghc,nkaretnikov/ghc,vTurbine/ghc,da-x/ghc,wxwxwwxxx/ghc,sdiehl/ghc,gridaphobe/ghc,oldmanmike/ghc,mettekou/ghc,nkaretnikov/ghc,TomMD/ghc,ml9951/ghc,AlexanderPankiv/ghc,fmthoma/ghc,bitemyapp/ghc,nushio3/ghc,gcampax/ghc,vTurbine/ghc,gcampax/ghc,oldmanmike/ghc,oldmanmike/ghc,olsner/ghc,nathyong/microghc-ghc,nkaretnikov/ghc,mettekou/ghc,fmthoma/ghc,anton-dessiatov/ghc,urbanslug/ghc,mettekou/ghc,da-x/ghc,shlevy/ghc,oldmanmike/ghc,AlexanderPankiv/ghc,nathyong/microghc-ghc,anton-dessiatov/ghc,green-haskell/ghc,da-x/ghc,acowley/ghc,nkaretnikov/ghc,forked-upstream-packages-for-ghcjs/ghc,nathyong/microghc-ghc,sgillespie/ghc,urbanslug/ghc,AlexanderPankiv/ghc,GaloisInc/halvm-ghc,ezyang/ghc,siddhanathan/ghc,sgillespie/ghc,sgillespie/ghc,ghc-android/ghc,gridaphobe/ghc,siddhanathan/ghc,anton-dessiatov/ghc,nathyong/microghc-ghc,sdiehl/ghc,urbanslug/ghc,urbanslug/ghc,tjakway/ghcjvm,christiaanb/ghc,snoyberg/ghc,green-haskell/ghc,tjakway/ghcjvm,wxwxwwxxx/ghc,siddhanathan/ghc,nushio3/ghc,forked-upstream-packages-for-ghcjs/ghc,da-x/ghc,shlevy/ghc,urbanslug/ghc,oldmanmike/ghc,ezyang/ghc,vikraman/ghc,ezyang/ghc,mcschroeder/ghc,ml9951/ghc,fmthoma/ghc,acowley/ghc,siddhanathan/ghc,mfine/ghc,acowley/ghc,ml9951/ghc,anton-dessiatov/ghc,anton-dessiatov/ghc,vTurbine/ghc,wxwxwwxxx/ghc,tjakway/ghcjvm,sdiehl/ghc,oldmanmike/ghc,wxwxwwxxx/ghc,vikraman/ghc,ml9951/ghc,olsner/ghc,mfine/ghc,shlevy/ghc,urbanslug/ghc,mfine/ghc,oldmanmike/ghc,shlevy/ghc,ghc-android/ghc,tjakway/ghcjvm,gridaphobe/ghc,nkaretnikov/ghc,TomMD/ghc,vTurbine/ghc,green-haskell/ghc,ghc-android/ghc,mfine/ghc,wxwxwwxxx/ghc,acowley/ghc,shlevy/ghc,elieux/ghc,GaloisInc/halvm-ghc,ezyang/ghc,AlexanderPankiv/ghc,elieux/ghc,christiaanb/ghc,bitemyapp/ghc,vikraman/ghc,nushio3/ghc,mfine/ghc,gcampax/ghc,tjakway/ghcjvm,mcschroeder/ghc,snoyberg/ghc,fmthoma/ghc,nkaretnikov/ghc,da-x/ghc,olsner/ghc,shlevy/ghc,elieux/ghc,gridaphobe/ghc,siddhanathan/ghc,mfine/ghc,snoyberg/ghc,nathyong/microghc-ghc,fmthoma/ghc,GaloisInc/halvm-ghc,sgillespie/ghc,da-x/ghc,olsner/ghc,acowley/ghc,vTurbine/ghc,green-haskell/ghc,ghc-android/ghc,nushio3/ghc,bitemyapp/ghc,elieux/ghc,ghc-android/ghc,TomMD/ghc,snoyberg/ghc,gridaphobe/ghc,ml9951/ghc