Taken from commit 8e407b62f2ed89fe41c40a976669df1693cf7027
in https://github.com/boundarydevices/linux-imx6

.

    cfg80211: Using new wiphy flag WIPHY_FLAG_DFS_OFFLOAD
    When flag WIPHY_FLAG_DFS_OFFLOAD is defined, the driver would handle
    all the DFS related operations. Therefore the kernel needs to ignore
    the DFS state that it uses to block the userspace calls to the
    driver through cfg8021 APIs. Also it should treat the userspace
    calls to start radar detection as a no-op.

Ref: BSP-65
Signed-off-by: Paul Barker <paul.barker@sancloud.com>