tracing: Fix output of set_event for some cached module events

tracing: Fix output of set_event for some cached module events

The following works fine:

 ~# echo ':mod:trace_events_sample' > /sys/kernel/tracing/set_event
 ~# cat /sys/kernel/tracing/set_event
 *:*:mod:trace_events_sample
 ~#

But if a name is given without a ':' where it can match an event name or
system name, the output of the cached events does not include a new line:

 ~# echo 'foo_bar:mod:trace_events_sample' > /sys/kernel/tracing/set_event
 ~# cat /sys/kernel/tracing/set_event
 foo_bar:mod:trace_events_sample~#

Add the '\n' to that as well.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20250121151336.6c491844@gandalf.local.home
Fixes: b355247df104e ("tracing: Cache ":mod:" events for modules not loaded yet")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>