Adding allocList function

This function iterates over the tryMGAlloc function, updates the node
list and instance list, and refeeds it recursively until no new
instances are left.

This allows us then to allocate multiple instances and see if they would
fit together.

Signed-off-by: René Nussbaumer <rn@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>