The reallocated part of the enlarged association array was left
uninitialized which would have resulted in trying to free random
pointers.
This was a theoretical bug because it wasn't possible to register
more than 32 cache types since no netlink family supports that
many individual cache types.
Nevertheless this patch fixes the bug and also reduces the default
size of the allocation table and expandations a bit to reduce the
memory footprint slightly.
adbc568735