pinctrl: actions: pinctrl-owl: Constify owl_pinctrl_ops and owl_pinmux_ops

pinctrl: actions: pinctrl-owl: Constify owl_pinctrl_ops and owl_pinmux_ops

The only usage of owl_pinctrl_ops and owl_pinmux_ops is to assign their
addresses to the pctlops and the pmxops fields in the pinctrl_desc struct,
which are const pointers. Make them const to allow the compiler to put them
in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200830224311.36994-2-rikard.falkeborn@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>