gru: initial GRU based on blade topology

Change the GRU initialization code to initialize based on blade topology
instead of node topology.  The result is the same but blade-based
initialization is cleaner.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>