(subst): Remove decls of unused variables ORIG_CODE.
(simplify_if_then_else): Remove decl of unused variable C2.
(make_compound_operation): Remove decl of unused variable COUNT.
(known_cond): Remove decl of unused variable NEW.
(make_field_assignment): Remove decl of unused variable OURDEST.
(simplify_and_const_int): Remove decls of unused variables.
(simplify_shift_const): Remove decl of unused variable INNER.

From-SVN: r6876