De-tabify and remove trailing whitespace

compiler/basicTypes/MkId.lhs

compiler/basicTypes/OccName.lhs

compiler/basicTypes/VarSet.lhs

compiler/coreSyn/CoreArity.lhs

compiler/coreSyn/CoreSyn.lhs

compiler/coreSyn/CoreUnfold.lhs

compiler/deSugar/DsArrows.lhs

compiler/deSugar/DsBinds.lhs

compiler/deSugar/DsUtils.lhs

compiler/deSugar/MatchCon.lhs

compiler/iface/BuildTyCl.lhs

compiler/iface/IfaceEnv.lhs

compiler/simplCore/FloatIn.lhs

compiler/simplCore/FloatOut.lhs

compiler/typecheck/FamInst.lhs

compiler/typecheck/Inst.lhs

compiler/typecheck/TcClassDcl.lhs

compiler/typecheck/TcDefaults.lhs

compiler/typecheck/TcErrors.lhs

compiler/typecheck/TcHsType.lhs