usb: gadget: bdc: fix typo in comment

Spelling mistake (triple letters) in comment.
Detected with the help of Coccinelle.

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Link: https://lore.kernel.org/r/20220521111145.81697-92-Julia.Lawall@inria.fr


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>