monitor: Decode device flags mgmt ops and event

monitor: Decode device flags mgmt ops and event

Add support for Get Device Flags and Set Device Flags mgmt operations
and Device Flags Changed mgmt event.

Sample trace:
@ MGMT Command: Set Device Flags (0x0050) plen 11     {0x0002} [hci0]
        LE Address: CD:F3:CD:13:C5:91 (Static)
        Current Flags: 0x00000000
@ MGMT Event: Device Flags Changed (0x002a) plen 15   {0x0001} [hci0]
        LE Address: CD:F3:CD:13:C5:91 (Static)
        Supported Flags: 0x00000001
          Remote Wakeup
        Current Flags: 0x00000000
@ MGMT Event: Device Flags Changed (0x002a) plen 15   {0x0004} [hci0]
        LE Address: CD:F3:CD:13:C5:91 (Static)
        Supported Flags: 0x00000001
          Remote Wakeup
        Current Flags: 0x00000000
@ MGMT Event: Device Flags Changed (0x002a) plen 15   {0x0003} [hci0]
        LE Address: CD:F3:CD:13:C5:91 (Static)
        Supported Flags: 0x00000001
          Remote Wakeup
        Current Flags: 0x00000000
@ MGMT Event: Command Complete (0x0001) plen 10       {0x0002} [hci0]
      Set Device Flags (0x0050) plen 7
        Status: Success (0x00)
        LE Address: CD:F3:CD:13:C5:91 (Static)

Signed-off-by: Anuj Jain <anuj01.jain@samsung.com>
Signed-off-by: Ayush Garg <ayush.garg@samsung.com>