Add sniff to require a $wpdb->prepare() to have a 2nd argument

[westonruter]

[JDGrimes]

Related: WP#22262.

[GaryJones]

Could we count the %s, %d etc. and make sure there's enough arguments to cover the placeholders?

[jrfnl]

Closing - the original issue is already covered. The remaining additional issues have been been added to a new ticket: #641

[jrfnl]

Definitively fixed in #1160