tools/bootconfig: Add tracing_on support to helper scripts

Add ftrace.instance.INSTANCE.tracing_on support to ftrace2bconf.sh
and bconf2ftrace.sh.

commit 8490db06 ("tracing/boot: Add per-instance tracing_on
option support") added the per-instance tracing_on option,
but forgot to update the helper scripts.

Link: https://lkml.kernel.org/r/160749166410.3497930.14204335886811029800.stgit@devnote2



Cc: stable@vger.kernel.org
Fixes: 8490db06 ("tracing/boot: Add per-instance tracing_on option support")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>