alias() macros.
(struct ia64_cursor): Rearrange order of members a bit to group
things that logicall belong together. Rename rp_loc to
ip_loc.
(struct ia64_unwind_table): Drop start and end members (they are now
in unw_ia64_table_t).
(struct ia64_reg_state): Break declaration out of declaration for
ia64_state_record and add "next" member.
(struct ia64_state_record): Add member "labeled_states", drop
members "stack", and "reg_state_list".
(Logical change 1.5)