Bluetooth: Fix advertising duplicated flags
Instances may have flags set as part of its data in which case the code
should not attempt to add it again otherwise it can cause duplication:
< HCI Command: LE Set Extended Advertising Data (0x08|0x0037) plen 35
Handle: 0x00
Operation: Complete extended advertising data (0x03)
Fragment preference: Minimize fragmentation (0x01)
Data length: 0x06
Flags: 0x04
BR/EDR Not Supported
Flags: 0x06
LE General Discoverable Mode
BR/EDR Not Supported
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>