b44: missing netif_wake_queue() in b44_open()

This patch fixes a problem plaguing Dell notebooks with built-in b44
ethernet: The driver refuses to transmit packets of any kind until after
the first 5-second tx_timeout occurs. This bug causes DHCP negotiation to
fail (timeout) during installation of Ubuntu Linux.

Signed-off-by: Mark Lord <lkml@rtr.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>