needsCDecl: remove extra equation for CaseLabel, which was overlapped
(and wrong!).
needsCDecl (PlainModuleInitLabel _ _) = True
needsCDecl ModuleRegdLabel = False
needsCDecl (PlainModuleInitLabel _ _) = True
needsCDecl ModuleRegdLabel = False
-needsCDecl (CaseLabel _ _) = False
needsCDecl (StringLitLabel _) = False
needsCDecl (AsmTempLabel _) = False
needsCDecl (RtsLabel _) = False
needsCDecl (StringLitLabel _) = False
needsCDecl (AsmTempLabel _) = False
needsCDecl (RtsLabel _) = False