Bluetooth: HCI: Reword `BT_BUF_ACL_*` description

Some part of the descriptions were wrong. Also, the description of
`BT_BUF_ACL_RX_SIZE` was too verbose and no longer needed with the
updated L2CAP documentation.

Signed-off-by: Théo Battrel <theo.battrel@nordicsemi.no>
1 file changed