Deny unused-extern-crates
Deny unused-extern-crates

No code changes are required and it's a sensible lint.

Signed-off-by: mulhern <7b51bcf507bcd7afb72bf8663752c0ddbeb517f6@redhat.com>

stratis-storage/stratisd,stratis-storage/stratisd,stratis-storage/stratisd