target: remove legacy target events

These events have been deprecated for a number of years, update any
remaining scripts to the new events.

Change-Id: Ic31ff388545ac8b3a500045699ca92c541b13f12
Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
Reviewed-on: http://openocd.zylin.com/634
Reviewed-by: Freddie Chopin <freddie.chopin@gmail.com>
Tested-by: jenkins
Reviewed-by: Bill Traynor <wmat@alphatroop.com>

doc/openocd.texi

@@ -4255,12 +4255,6 @@ depending on whether the breakpoint is in RAM or read only memory.
 @* Before the target steps, gdb is trying to start/resume the target
 @item @b{halted}
 @* The target has halted
-@ignore
-@item @b{old-gdb_program_config}
-@* DO NOT USE THIS: Used internally
-@item @b{old-pre_resume}
-@* DO NOT USE THIS: Used internally
-@end ignore
 @item @b{reset-assert-pre}
 @* Issued as part of @command{reset} processing
 after @command{reset_init} was triggered