* fix --help message
Commit 7b72c20f89 added help text for the
--cve switch, and the "can be specified multiple times" note got
associated with the --cve switch instead of staying with the --variant
switch. Restore the line to belong to the --variant switch help
message.
* Add new variants to error message
Commit 8e870db4f5 added new variants but
did not add them to the error message that listed the allowable
variants. Add them now.
