zpool(1M) import syntax for listing pools is different between synopsis and description
Synopsis currently lists the following form:
zpool import [-d dir] [-D]
while description also lists the -c cachefile option:
zpool import [-d dir | -c cachefile] [-D]
We either need to add -c option to synopsis, or, if it isn't really usable while listing pools that can be imported, remove it from description.
No data to display