treewide: use the generic board_name function

Use the generic function instead ot the target specific ones.

Signed-off-by: Mathias Kresin <dev@kresin.me>

target/linux/ipq806x/base-files/etc/hotplug.d/ieee80211/10_fix_wifi_mac

@@ -6,10 +6,10 @@ PHYNBR=${DEVPATH##*/phy}
 
 [ -n $PHYNBR ] || exit 0
 
-. /lib/ipq806x.sh
+. /lib/functions.sh
 . /lib/functions/system.sh
 
-board=$(ipq806x_board_name)
+board=$(board_name)
 
 case "$board" in
 	c2600)