Simplify and fix pull retransmission: * drop the valid field from block descriptor, use the existing bitmask instead * check whether the frame came into the second block before requesting the   first block again
Simplify and fix pull retransmission:
* drop the valid field from block descriptor, use the existing bitmask instead
* check whether the frame came into the second block before requesting the
  first block again



git-svn-id: 29c1264a5cf5e3532df57b06678e7347571c1a3c@830 f1ba3bf5-cb5c-402b-92a9-7c6bdc83a356

ananos/xen2mx,ananos/xen2mx,ananos/xen2mx,ananos/open-mx,ananos/open-mx,ananos/xen2mx,ananos/open-mx