pinctrl: imx: Split imx_pinctrl_set_state_scu() from imx_pinctrl_set_state_mmio()

pinctrl: imx: Split imx_pinctrl_set_state_scu() from imx_pinctrl_set_state_mmio()

Call imx_pinctrl_set_state_common() from imx_pinctrl_scu_conf_pins(),
rename imx_pinctrl_scu_conf_pins() to imx_pinctrl_set_state_scu().
Get rid of the unnecessary ifdeffery in pinctrl-imx.h in the process.
Remove all SCU support from pinctrl-imx.c imx_pinctrl_set_state_mmio()
which makes that function a pure MMIO pinctrl configuration accessor.
Update pinctrl-imx8.c to call imx_pinctrl_set_state_scu directly.

No functional change.

This patch is best viewed with git show -w due to indent change.

Signed-off-by: Marek Vasut <marex@denx.de>