pinctrl: rockchip: rk3328: Fix the correct routing config
If the gmac-m1 optimization(bit10) is selected, the gpio function
of gmac pins is not valid. We may use the rmii mode for gmac interface,
the pins such as rx_d2, rx_d3, which the rgmii mode used, but rmii not
used could be taken as gpio function. So gmac_rxd0m1 selects the bit2,
and gmac_rxd0m3 select bit10 is more correct.