tty: n_gsm: Delete unneeded semicolon

Delete the unneeded semicolon after curly braces.

Signed-off-by: Shaomin Deng <dengshaomin@cdjrlc.com>
Link: https://lore.kernel.org/r/20221105152656.4638-1-dengshaomin@cdjrlc.com


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