Main objective to remove the dependency to ti_pinmux_padconf_set/get function due to D41896 needs a generic driver for pinctrl-single without TI specific code, so there will be a chain of changes to get that up'n'running and this is one of them.

Another reason for this is to have one way to do the configuration and I think we have choosen the devicetree way.

todo:
Fix documentation /usr/src/share/man/man4/man4.arm/am335x_dmtpps.4
Fix overlay DTS example