arm64: a37xx: dts: Correct mpp definitions

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 <[email protected]>
Tested-by: iSoC Platform CI <[email protected]>
Cc: Simon Glass <[email protected]>
Cc: Stefan Roese <[email protected]>
Signed-off-by: Ken Ma <[email protected]>
Signed-off-by: Stefan Roese <[email protected]>