gemini: Use library functions to assign MAC address

This simplifies the ethernet address extraction script
by using standard library functions to locate the MTD
partitions and extract ethernet address from a binary
offset location in the flash. Furthermore, the aging
ifconfig is replaced by the ip tool, which will now
assign the MAC addresses.

Suggested-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
[ifconfig replacement, use -n instead of ! -z,
-n requires string to be quoted within the test brackets,
drop prepended "x" in check, add quotes, make local
variables local, kill whitespaces]

target/linux/gemini/base-files/lib/preinit/05_set_ether_mac_gemini

 #!/bin/sh
 
+. /lib/functions.sh
+. /lib/functions/system.sh
+
 set_ether_mac() {
+	local part
+	local DEVID
+	local MAC1
+	local MAC2
+
 	# Most devices have a standard "VCTL" partition
-	CONFIG_PARTITION="$(grep "VCTL" /proc/mtd | cut -d: -f1)"
-	if [ ! -z $CONFIG_PARTITION ] ; then
-		MAC1="$(strings /dev/$CONFIG_PARTITION |grep MAC|cut -d: -f2|cut -c3-14|sed -e 's,\(..\),:\1,g' -e 's,^:,,')"
-		MAC2="$(strings /dev/$CONFIG_PARTITION |grep MAC|cut -d: -f8|cut -c3-14|sed -e 's,\(..\),:\1,g' -e 's,^:,,')"
+	part="$(find_mtd_part VCTL)"
+	if [ -n "$part" ]; then
+		MAC1="$(strings $part |grep MAC|cut -d: -f2|cut -c3-14|sed -e 's,\(..\),:\1,g' -e 's,^:,,')"
+		MAC2="$(strings $part |grep MAC|cut -d: -f8|cut -c3-14|sed -e 's,\(..\),:\1,g' -e 's,^:,,')"
 
-		ifconfig eth0 hw ether $MAC1 2>/dev/null
-		ifconfig eth1 hw ether $MAC2 2>/dev/null
+		ip link set eth0 address "$MAC1" 2>/dev/null
+		ip link set eth1 address "$MAC2" 2>/dev/null
 		return 0
 	fi
 
 	# The DNS-313 has a special field in its RedBoot
 	# binary that we need to check
-	CONFIG_PARTITION="$(grep "RedBoot" /proc/mtd | cut -d: -f1)"
-	if [ ! -z $CONFIG_PARTITION ] ; then
-		DEVID="$(dd if=/dev/mtdblock0 bs=1 skip=119508 count=7 2>/dev/null)"
-		if [ "x$DEVID" = "xdns-313" ] ; then
-			MAC1="$(dd if=/dev/mtdblock0 bs=1 skip=119540 count=6 2>/dev/null | hexdump -n6 -e '/1 ":%02X"' | sed s/^://g)"
-			ifconfig eth0 hw ether $MAC1 2>/dev/null
+	part="$(find_mtd_part RedBoot)"
+	if [ -n "$part" ]; then
+		DEVID="$(dd if=$part bs=1 skip=119508 count=7 2>/dev/null)"
+		if [ "$DEVID" = "dns-313" ]; then
+			MAC1="$(mtd_get_mac_binary RedBoot 119540)"
+			ip link set eth0 address "$MAC1" 2>/dev/null
 			return 0
 		fi
 	fi