tracing: Remove pid in task_rename tracing output

tracing: Remove pid in task_rename tracing output

Remove pid in task_rename tracepoint output, since that tracepoint only
deals with the current task, and is printed by default. This also saves
some space in the entry and avoids wasted padding.

Link: https://lkml.kernel.org/r/20241105120247.596a0dc9@gandalf.local.home
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20241108113455.2924361-2-elver@google.com
Signed-off-by: Kees Cook <kees@kernel.org>