client data generated by ext2spice and attached to a node's
nodeClient record; there is an initNodeClient() routine but no
corresponding freeNodeClient() routine. Eventually had to add a
callback function passed to EFDone() and EFFlatDone() to clean up
these entries. After doing that, valgrind reports clean for all
memory allocated within ext2spice (there are other things that are
not freed but not related to a specific command, so do not need to
be treated as leaks).
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