board: fsl: lx2160a: Fix the loop in board_fix_fdt function

Fix loop in board_fix_fdt that erroneously increments the counter
in all cases whereas the counter should be incremented only if a
matching string has been found.

Fixes: 5d535aa4 ("board: fsl: lx2160a: implement board_fix_fdt")

Signed-off-by: Pankaj Bansal <pankaj.bansal@nxp.com>
Signed-off-by: Priyanka Jain <priyanka.jain@nxp.com>