USB: ftdi_sio: make port probe less verbose

There's no need to print the number of endpoints per interface or
endpoint wMaxPacketSize during port probe. This information is readily
available using lsusb should it ever be needed.

Note that this also fixes the wMaxPacketSize being incorrectly reported
on big-endian systems due to a missing le16_to_cpu().

Signed-off-by: Johan Hovold <johan@kernel.org>