Bluetooth: ISO: Fix getname not returning broadcast fields

getname shall return iso_bc fields for both BIS_LINK and PA_LINK since
the likes of bluetoothd do use the getpeername to retrieve the SID both
when enumerating the broadcasters and when synchronizing.

Fixes: a7bcffc6 ("Bluetooth: Add PA_LINK to distinguish BIG sync and PA sync connections")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>