Accton AS5610_52X: Correct GPIO (pca9506) nodes in DTS

There are 4 wrong GPIO nodes in DTS.  It showes error messages during
kernel booting:

    pca953x 17-0071: failed reading register
    pca953x 17-0072: failed reading register
    pca953x 17-0073: failed reading register

According to the HW spec, these 4 nodes are pca9506.