Bluetooth: Fix SMP pairing method selection

The tk_request function takes the local IO capability as the second last
parameter and the remote IO capability as the last parameter. They were
previously swapped: when we receive a pairing response
req->io_capability contains the local one and rsp->io_capability the
remote one.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>