We wanted to exit the loop with "div" set to zero, but instead, if we
don't hit the break then "div" is -1 when we finish the loop.  It leads
to an array underflow a few lines later.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
         *  Look for the greatest clock divisor that allows an 
         *  input speed faster than the period.
         */
-       while (div-- > 0)
+       while (--div > 0)
                if (kpc >= (div_10M[div] << 2)) break;
 
        /*