arm: mvebu: turris_omnia: Implement getting board information from MCU

Implement reading board serial number, first MAC address and board
version from MCU. MCU supports board information if the FEAT_BOARD_INFO
feature bit is set in MCU features.

Prefer getting board information from MCU if supported, fallback to
Atmel SHA chip.

Signed-off-by: Marek BehĂșn <kabel@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/board/CZ.NIC/turris_omnia/Makefile b/board/CZ.NIC/turris_omnia/Makefile
index dc39b44..341378b 100644
--- a/board/CZ.NIC/turris_omnia/Makefile
+++ b/board/CZ.NIC/turris_omnia/Makefile
@@ -2,4 +2,4 @@
 #
 # Copyright (C) 2017 Marek Behún <kabel@kernel.org>
 
-obj-y	:= turris_omnia.o ../turris_atsha_otp.o
+obj-y	:= turris_omnia.o ../turris_atsha_otp.o ../turris_common.o