test - Adjust vnodeinfo for recent kernel changes

* Adjust vnodeinfo for recent kernel changes
kernel - Fix hammer flush-during-reclaim bug

* hammer was improperly using vn_unlock/vn_lock to temporarily unlock a
  vnode.  If this is done during a reclaim vn_lock() will fail, resulting
  in a locking mismatch.

* Use vx_unlock/vx_lock instead, and also check for the reclaim by checking
  the VRECLAIMED flag rather than the VINACTIVE flag.  VINACTIVE might not
  yet be set.
kernel - Cleanup vfs_lock & ref-count states states

* Clean up vp->v_state state transitions

* Fix bugs in the cachedvnodes counter tracking.  v_refcnt has to
  be masked against VREF_MASK to detect non-zero->0 and 0->non-zero
  transitions properly.

* Clear VREF_FINALIZE when reactivating a vnode in vget().

* vhold()/vdrop() no longer prevent a vnode from being moved to the
  vinactive list.  They simply prevent reclamation.

* Adjust the vnlru trigger points a bit.

* When cleaning, leave the vnode on the inactive list until we determine
  we can destroy it.  Add a ref instead of using the VREF_TERMINATE
  placeholding ref (since the vnode is still on the list).

* Implement vnode->v_act and remove the inactive mid-point stuff.  The
  now is that vnodes are selectively moved from the active list to
  the inactive list as needed.  Inactive vnodes are then cleaned up in order.

* Adjust hysteresis so that vnlru has a better chance of handling the
  vnode garbage collection before we forced it to be done synchronously
  in userexit.
mxge: Make sure RX data size is cache line size aligned

Currently even without the __cachealign, RX data struct size is properly
aligned on 2 cache line size.  Add __cachealign, so that even if some
debugging fields are added, RX data struct size still will be cache line
size aligned.
test: Test commit from orb
mxge: Record RX slot count instead of its size

Original code assumes that the total size of RX slots is same as one RX
descriptor ring size.  This assumption could easily be broken if we ask
chip to deliver RSS hash (RX slot size will be changed from 4 bytes to 8
bytes).  RX slot count is recorded now.