* infptrace.c: Remove #ifdef'ed out inclusion of gdb_stat.h.

* infptrace.c: Remove #ifdef'ed out inclusion of gdb_stat.h.
Reorder includes.
(fetch_register, store_register): Remove prototypes.
(child_resume): Reorganize code and comments such that it is
grouped a bit more logically.
(attach): Explicitly compare errno against 0.
(detach): Likewise.  Use perror_with_name instead of
print_sys_errmsg.
* Makefile.in (infptrace.o): Update dependencies.