file: fix files not getting pruned

file: fix files not getting pruned

When the filedata logger is enabled (file extraction), but a file is not
stored due to no rules matching to force this, the file would never be
freed.

This was caused by a check in the file pruning logic that only freed a
file when the FILE_STORED flag was set. However files can also have the
FILE_NOSTORE flag set which indicates that a file won't be stored.

This patch makes sure that both conditions lead to file pruning.