Bluetooth: Fix LE MTU reporting for HCIGETDEVINFO

This patch fixes the use of le_mtu and le_pkts values in the
HCIGETDEVINFO ioctl for LE-only controllers.

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>