Since limited tracking device per condition, this feature is to support
tracking multiple devices concurrently.
When a pattern monitor detects the device, this feature issues an address
monitor for tracking that device. Let pattern monitor can keep monitor
new devices.
This feature adds an address filter when receiving a LE monitor device
event which monitor handle is for a pattern, and the controller started
monitoring the device. And this feature also has cancelled the monitor
advertisement from address filters when receiving a LE monitor device
event when the controller stopped monitoring the device specified by an
address and monitor handle.

Below is an example to know the feature adds the address filter.

//Add MSFT pattern monitor
< HCI Command: Vendor (0x3f|0x00f0) plen 14          #142 [hci0] 55.552420
        03 b8 a4 03 ff 01 01 06 09 05 5f 52 45 46        .........._REF
> HCI Event: Command Complete (0x0e) plen 6          #143 [hci0] 55.653960
      Vendor (0x3f|0x00f0) ncmd 2
        Status: Success (0x00)
        03 00

//Got event from the pattern monitor
> HCI Event: Vendor (0xff) plen 18                   #148 [hci0] 58.384953
        23 79 54 33 77 88 97 68 02 00 fb c1 29 eb 27 b8  #yT3w..h....).'.
        00 01                                            ..

//Add MSFT address monitor (Sample address: B8:27:EB:29:C1:FB)
< HCI Command: Vendor (0x3f|0x00f0) plen 13          #149 [hci0] 58.385067
        03 b8 a4 03 ff 04 00 fb c1 29 eb 27 b8           .........).'.

//Report to userspace about found device (ADV Monitor Device Found)
@ MGMT Event: Unknown (0x002f) plen 38           {0x0003} [hci0] 58.680042
        01 00 fb c1 29 eb 27 b8 01 ce 00 00 00 00 16 00  ....).'.........
        0a 09 4b 45 59 42 44 5f 52 45 46 02 01 06 03 19  ..KEYBD_REF.....
        c1 03 03 03 12 18                                ......

//Got event from address monitor
> HCI Event: Vendor (0xff) plen 18                   #152 [hci0] 58.672956
        23 79 54 33 77 88 97 68 02 00 fb c1 29 eb 27 b8  #yT3w..h....).'.
        01 01
Signed-off-by: Alex Lu <alex_lu@realsil.com.cn>
Signed-off-by: Hilda Wu <hildawu@realtek.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>