Bluetooth: Use voice setting in deferred SCO connection request

When an incoming eSCO connection is requested, check the selected voice
setting and reply appropriately. Voice setting should have been
negotiated previously.  For example, in case of HFP, the codec is
negotiated using AT commands on the RFCOMM channel. This patch only
changes replies for socket with deferred setup enabled.

Signed-off-by: Frédéric Dalleau <frederic.dalleau@linux.intel.com>
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>