* armnbsd-nat.c: Include "gdb_string.h" and "inf_ptrace.h".

* armnbsd-nat.c: Include "gdb_string.h" and "inf_ptrace.h".
Reorder includes.  Don't require FETCH_INFERIOR_REGISTERS to be
defined.
(armnbsd_fetch_registers): Rename from armnbsd_fetch_registers.
Make static.
(armnbsd_store_registers): Rename from armnbsd_store_registers.
Make static.
(_initialize_arm_netbsd_nat): Construct and add target vector.
* Makefile.in (armnbsd-nat.o): Update dependencies.
* config/arm/nbsdaout.mh (NATDEPFILES): Remove infptrace.o and
intarg.o, add inf-ptrace.o.
(NAT_FILE): Set to solib.h.
* config/arm/nbsdelf.mh (NATDEPFILES): Remove infptrace.o and
inftarg.o, add inf-ptrace.o.
(NAT_FILE): Remove.