Linux gdbserver fork event debug output

Linux gdbserver fork event debug output

The "extended event with waitstatus" debug output is unreachable, as
it is guarded by "if (!report_to_gdb)".  If extended_event_reported is
true, then so is report_to_gdb.  Move it to where we print why we're
reporting an event to GDB.

Also, the debug output currently tries to print the wrong struct
target_waitstatus.

gdb/gdbserver/ChangeLog:
2015-08-06  Pedro Alves  <palves@redhat.com>

	* linux-low.c (linux_wait_1): Move fork event output out of the
	!report_to_gdb check.  Pass event_child->waitstatus to
	target_waitstatus_to_string instead of ourstatus.