re PR c++/21166 (g++ gives error on reference to packed structure elements)

.:	PR c++/21166
	* c-decl.c (finish_struct):  Only set DECL_PACKED on a field
	when its natural alignment is > BITS_PER_UNIT.
	* stor-layout.c (finalize_type_size): Revert my patch of 2005-08-08.
	* c-common.c (handle_packed_attribute): Ignore packing on a field
	whose type is naturally char aligned.
cp:
	PR c++/21166
	* class.c (check_field_decls): Only set DECL_PACKED on a field
	when its natural alignment is > BITS_PER_UNIT.

From-SVN: r107599