Allocate larger buffers for unsent updates.
Allocate larger buffers for unsent updates.

We used to allocate enough buffer space to send one full-size frame.
Unfortunately, in large networks this causes our update coalescing
strategy to fail, just where it is the most useful.  Allocate enough
buffers to fit a full update.

wlanslovenija/babeld,sudomesh/babeld,dtaht/babeld-shortrtt-metrics,woniullb/babeld,tcatm/babeld,jech/babeld,Drooids/babeld,Gwendocg/babeldToS,wlanslovenija/babeld,jech/babeld,Gwendocg/babeldToS,boutier/babeld