iomux-v3: Take mx6dqp in consideration for imx_iomux_v3_setup_pad()

We should take the MX6DP and MX6QP options in consideration
when defining imx_iomux_v3_setup_pad().

Based on a patch by Pierluigi Passaro <pierluigi.p@variscite.com>

Signed-off-by: Eran Matityahu <eran.m@variscite.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>