* infrun.c (stop_registers): Change variable's type to ``struct

* infrun.c (stop_registers): Change variable's type to ``struct
regcache'''.
(xmalloc_inferior_status): Delete function.
(free_inferior_status): Delete function.
(normal_stop): Use regcache_cpy.
(struct inferior_status): Change type of fields ``stop_registers''
and ``registers'' to ``struct regcache''.
(write_inferior_status_register): Use regcache_write.
(save_inferior_status): Instead of calling
xmalloc_inferior_status, allocate the inf_status buffer directly.
Use regcache_dup_no_passthrough and regcache_dup to save the
buffers.
(restore_inferior_status): Use regcache_xfree and regcache_cpy.
Replace the stop_registers regcache instead of overriding it.  Use
regcache_xfree.  Instead of calling free_inferior_status, xfree
the buffer directly.
(discard_inferior_status): Use regcache_xfree.  Instead of calling
free_inferior_status, xfree the buffer directly.
(build_infrun): Use regcache_xmalloc.
(_initialize_infrun): Delete redundant call to build_infrun.
* Makefile.in (infcmd.o): Add $(regcache_h).
* infcmd.c: Include "regcache.h".
(run_stack_dummy): Use deprecated_grub_regcache_for_registers to
obtain the address of `stop_registers' register buffer.
(print_return_value): Ditto.
* inferior.h (struct regcache): Add opaque declaration.
(stop_registers): Change variable's declared type to ``struct
regcache''.