vxge: Wait for Rx to become idle before reseting or closing

Wait for the receive traffic to become idle before attempting to close
or reset the adapter.  To enable the processing of packets while Receive
Idle, move the clearing of __VXGE_STATE_CARD_UP bit in vxge_close to
after it.  Also, modify the return value of the ISR when the adapter is
down to IRQ_HANDLED.  Otherwise there are unhandled interrupts for the
device.

Signed-off-by: Jon Mason <jon.mason@exar.com>
Signed-off-by: Ram Vepa <ram.vepa@exar.com>
Signed-off-by: David S. Miller <davem@davemloft.net>