pinctrl: imx: Split imx_pinctrl_probe() into common and mmio parts

Split imx_pinctrl_probe() into imx_pinctrl_probe_common() and
imx_pinctrl_probe_mmio(). The former does the common setup, the
later does the common setup and MMIO access configuration. The
common setup can be used as-is for SCU based systems, update
the pinctrl-imx8 to call only the common setup, update all the
other pinctrl drivers to call imx_pinctrl_probe_mmio().

No functional change.

Signed-off-by: Marek Vasut <marex@denx.de>
diff --git a/drivers/pinctrl/nxp/pinctrl-imx6.c b/drivers/pinctrl/nxp/pinctrl-imx6.c
index ae16ce7..495b6af 100644
--- a/drivers/pinctrl/nxp/pinctrl-imx6.c
+++ b/drivers/pinctrl/nxp/pinctrl-imx6.c
@@ -40,7 +40,7 @@
 	.name = "fsl_imx6q_iomuxc",
 	.id = UCLASS_PINCTRL,
 	.of_match = of_match_ptr(imx6_pinctrl_match),
-	.probe = imx_pinctrl_probe,
+	.probe = imx_pinctrl_probe_mmio,
 	.remove = imx_pinctrl_remove,
 	.priv_auto	= sizeof(struct imx_pinctrl_priv),
 	.ops = &imx6_pinctrl_ops,