This patch adds support for advertising in primary and secondary
channel on different PHYs. User can add the phy preference in
the flag based on which phy type will be added in extended
advertising parameter would be set.

@ MGMT Command: Add Advertising (0x003e) plen 11
        Instance: 1
        Flags: 0x00000200
          Advertise in CODED on Secondary channel
        Duration: 0
        Timeout: 0
        Advertising data length: 0
        Scan response length: 0
< HCI Command: LE Set Extended Advertising Enable (0x08|0x0039) plen 2
        Extended advertising: Disabled (0x00)
        Number of sets: Disable all sets (0x00)
> HCI Event: Command Complete (0x0e) plen 4
      LE Set Extended Advertising Enable (0x08|0x0039) ncmd 2
        Status: Success (0x00)
< HCI Command: LE Set Extended Advertising Parameters (0x08|0x0036) plen 25
        Handle: 0x00
        Properties: 0x0000
        Min advertising interval: 1280.000 msec (0x0800)
        Max advertising interval: 1280.000 msec (0x0800)
        Channel map: 37, 38, 39 (0x07)
        Own address type: Random (0x01)
        Peer address type: Public (0x00)
        Peer address: 00:00:00:00:00:00 (OUI 00-00-00)
        Filter policy: Allow Scan Request from Any, Allow Connect Request from Any (0x00)
        TX power: 127 dbm (0x7f)
        Primary PHY: LE Coded (0x03)
        Secondary max skip: 0x00
        Secondary PHY: LE Coded (0x03)
        SID: 0x00
        Scan request notifications: Disabled (0x00)
Signed-off-by: Jaganath Kanakkassery <jaganathx.kanakkassery@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>