Spell "transmission" properly.

Found by searching for keyword "tranm".
Signed-off-by: Yueh-Shun Li <shamrocklee@posteo.net>
Link: https://lore.kernel.org/r/20230622012627.15050-3-shamrocklee@posteo.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>