* inf-child.c (inf_child_follow_fork): Add OPS argument.

	* inf-child.c (inf_child_follow_fork): Add OPS argument.
	* inf-ptrace.c (inf_ptrace_follow_fork): Likewise.
	* inf-ttrace.c (inf_ttrace_follow_fork): Likewise.
	* inftarg.c (child_follow_fork): Likewise.
	* linux-nat.c (child_follow_fork): Likewise.  Use ops instead of
	&deprecated_child_ops.
	* target.c (update_current_target): Do not inherit to_follow_fork.
	(target_follow_fork): New function.
	(debug_to_follow_fork): Remove.
	(setup_target_debug): Don't set to_follow_fork.
	* target.h (struct target_ops): Add struct target_ops * to
	to_follow_fork.
	(child_follow_fork): Add struct target_ops * argument.
	(target_follow_fork): Replace macro with prototype.