Remove ignoring leading exec events code.

	Remove ignoring leading exec events code.
        * fork-child.c (startup_inferior): Do not set
        inferior_ignoring_leading_exec_events.
        * inf-child.c (inf_child_reported_exec_events_per_exec_call): Remove.
        (inf_child_target): Do not set to_reported_exec_events_per_exec_call.
        * infrun.c (inferior_ignoring_leading_exec_events): Remove.
        (handle_inferior_event): Remove code for ignoring leading exec
        events.
        * target.c (update_current_target): Do not inherit, or default,
        to_reported_exec_events_per_exec_call.
        (debug_to_reported_exec_events_per_exec_call): Remove.
        (setup_target_debug): Do not set to_reported_exec_events_per_exec_call.
        * target.h (target_reported_exec_events_per_exec_call): Remove.
        (struct target): Remove the to_reported_exec_events_per_exec_call
        field.