Bluetooth: Remove mgmt_rp_read_local_oob_ext_data struct

This extended return parameters struct conflicts with the new Read Local
OOB Extended Data command definition. To avoid the conflict simply
rename the old "extended" version to the normal one and update the code
appropriately to take into account the two possible response PDU sizes.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>