* config/ppc-tdep.h (struct gdbarch_tdep): Delete

* config/ppc-tdep.h (struct gdbarch_tdep): Delete
'ppc_gplast_regnum' member.
(ppc_num_gprs): New enum constant.
* ppc-linux-nat.c (ppc_register_u_addr): Use tdep->ppc_gp0_regnum
and ppc_num_gprs instead of tdep->ppc_gplast_regnum.
* rs6000-nat.c (regmap, fetch_inferior_registers,
store_inferior_registers): Same.
* rs6000-tdep.c (e500_pseudo_register_read)
(e500_pseudo_register_write): Same.
(rs6000_gdbarch_init): Don't initialize tdep->ppc_gplast_regnum.