Flags documentation: -fwarn-unrecognized-pragmas is enabled by -Wall (#6050)
Flags documentation: -fwarn-unrecognized-pragmas is enabled by -Wall (#6050)

MERGED from commit 44098b3dab032a83cc869855de67377f41d82384

ilyasergey/GHC-XAppFix,ilyasergey/GHC-XAppFix,ilyasergey/GHC-XAppFix,ilyasergey/GHC-XAppFix