[PATCH] USB: pl2303_update_line_status data length fix

Minimum data length must be UART_STATE + 1, as data[UART_STATE] is being
accessed for the new line_state. Although PL-2303 hardware is not
expected to send data with exactly UART_STATE length, this keeps it on
the safe side.

Signed-off-by: Horst Schirmeier <horst@schirmeier.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>