mfd: tps65911-comparator: Fix an off by one bug

The COMP1 and COMP2 elements are in 0 and 1 respectively so this code is
accessing the wrong elements and one space beyond the end of the array.

The "id" variable is never COMP (0) so that code can be removed.

Fixes: 6851ad3a ("TPS65911: Comparator: Add comparator driver")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>