Bluetooth: host: hci_core: handle additional error code

Some Bluetooth controllers (Nordic Softdevice) now use
`BT_HCI_ERR_INSUFFICIENT_RESOURCES` to signify when advertising sets
cannot be created, instead of the old `BT_HCI_ERR_CONN_LIMIT_EXCEEDED`.

Signed-off-by: Jordan Yates <jordan.yates@data61.csiro.au>