treewide: move calibration data extraction function to library

This moves the almost identical calibration data extraction
functions present multiple times in several targets to a single
library file /lib/functions/caldata.sh.

Functions are renamed with more generic names to merge different
variants that only differ in their names.

Most of the targets used find_mtd_chardev, while some used
find_mtd_part inside the extraction code. To merge them, the more
abundant version with find_mtd_chardev is used in the common code.

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
[rebase on latest master; add mpc85xx]
Signed-off-by: David Bauer <mail@david-bauer.net>

target/linux/brcm63xx/base-files/etc/hotplug.d/firmware/10-rt2x00-eeprom

@@ -1,28 +1,9 @@
 #!/bin/sh
 # Based on gabors ralink wisoc implementation.
 
-rt2x00_eeprom_die() {
-	echo "rt2x00 eeprom: " "$*"
-	exit 1
-}
-
-rt2x00_eeprom_extract() {
-	local part=$1
-	local offset=$(($2))
-	local count=$(($3))
-	local mtd
-
-	mtd=$(find_mtd_part $part)
-	[ -n "$mtd" ] || \
-		rt2x00_eeprom_die "no mtd device found for partition $part"
-
-	dd if=$mtd of=/lib/firmware/$FIRMWARE bs=1 skip=$offset count=$count || \
-		rt2x00_eeprom_die "failed to extract from $mtd"
-}
-
 [ -e /lib/firmware/$FIRMWARE ] && exit 0
 
-. /lib/functions.sh
+. /lib/functions/caldata.sh
 
 board=$(board_name)
 
@@ -30,14 +11,14 @@ case "$FIRMWARE" in
 "rt2x00.eeprom" )
 	case $board in
 	hg556a_c)
-		rt2x00_eeprom_extract "cal_data" 0x1fe00 0x200
+		caldata_extract "cal_data" 0x1fe00 0x200
 		;;
 	hg622 |\
 	hg655b)
-		rt2x00_eeprom_extract "cal_data" 0x0 0x200
+		caldata_extract "cal_data" 0x0 0x200
 		;;
 	*)
-		rt2x00_eeprom_die "board $board is not supported yet"
+		caldata_die "board $board is not supported yet"
 		;;
 	esac
 	;;