Documentation/trace: Fixed typos in the ftrace FLAGS section

Fixed typos in the FTRACE_OPS_FL_RECURSION flag description.

Signed-off-by: Matthew Cassell <mcassell411@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20231223185845.2326-1-mcassell411@gmail.com