USB: serial: ir-usb: fix big-endian baud-rate debug printk

Add missing endianness conversion when printing the supported baud
rates.

Found using sparse:

	warning: restricted __le16 degrades to integer

Fixes: e0d795e4

 ("usb: irda: cleanup on ir-usb module")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>