arm64: a37xx: dts: Correct mpp definitions

This patch corrects below mpp definitions for armada 3720 DB board
and ESPRESSOBin board:
- "smi" pins group is added and "smi" function is set for eth0;
- Now pcie pins are used as gpio to implement PCIe function in
  hardware, so "pcie" group function is changed to "gpio".

Reviewed-on: http://vgitil04.il.marvell.com:8080/43287
Reviewed-by: Hua Jing <jinghua@marvell.com>
Tested-by: iSoC Platform CI <ykjenk@marvell.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Stefan Roese <sr@denx.de>
Signed-off-by: Ken Ma <make@marvell.com>
Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/arch/arm/dts/armada-37xx.dtsi b/arch/arm/dts/armada-37xx.dtsi
index d139a61..301f9ee 100644
--- a/arch/arm/dts/armada-37xx.dtsi
+++ b/arch/arm/dts/armada-37xx.dtsi
@@ -183,6 +183,11 @@
 					function = "mii";
 				};
 
+				smi_pins: smi-pins {
+					groups = "smi";
+					function = "smi";
+				};
+
 				sdio_pins: sdio-pins {
 					groups = "sdio_sb";
 					function = "sdio";
@@ -190,7 +195,7 @@
 
 				pcie_pins: pcie-pins {
 					groups = "pcie1";
-					function = "pcie";
+					function = "gpio";
 				};
 			};