rv: Remove trailing whitespace from tracepoint string

RV event tracepoints print a line with the format:
    "event_xyz: S0 x event -> S1 "
    "event_xyz: S1 x event -> S0 (final)"

While printing an event leading to a non-final state, the line
has a trailing white space (visible above before the closing ").

Adapt the format string not to print the trailing whitespace if we are
not printing "(final)".

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250728135022.255578-3-gmonaco@redhat.com


Reviewed-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>