I think the qq// needs to be replaced with parenthesis. That's inside the quoted string so perl isn't going to do anything special with it. What's trying to happen there is a subselect which your version of MySQL may not support unless it is very recent. The subselect should be in parethesis. Try the following.

$rows = $dbh->do("UPDATE checkin
        SET    destination =
        (SELECT destination
        FROM checkin
        WHERE firstname='Henry' AND lastname='Rollins')
        WHERE  firstname='Bill' AND lastname='Gates'
") || die "Couldn't insert record : $DBI::errstr";
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---
print map { my ($m)=1<<hex($_)&11?' ':'';
$m.=substr('AHJPacehklnorstu',hex($_),1) }
split //,'2fde0abe76c36c914586c';
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