datapath: vxlan: Only set has-GBP bit in header if any other bits would be set

datapath: vxlan: Only set has-GBP bit in header if any other bits would be set

    vxlan: Only set has-GBP bit in header if any other bits would be set

    This allows for a VXLAN-GBP socket to talk to a Linux VXLAN socket by
    not setting any of the bits.

    Signed-off-by: Thomas Graf <tgraf@suug.ch>
    Signed-off-by: David S. Miller <davem@davemloft.net>
Upstream: db79a621835e ("vxlan: Only set has-GBP bit in header if any other bits would be set")
Signed-off-by: Thomas Graf <tgraf@noironetworks.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>