nft-qos: Update init script

This replaces the use of uci_validate_section() with
uci_load_validate(), which removes the need to declare local variables
for every config option.

This also adds a validate section to service_triggers(), and fixes some
variable name typos in qosdef_init_static().

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

net/nft-qos/files/lib/priority.sh

@@ -9,6 +9,12 @@
 P1=""; P2=""; P3=""; P4=""; P5=""; P6="";
 P7=""; P8=""; P9=""; P10=""; P11="";
 
+qosdef_validate_priority() {
+	uci_load_validate nft-qos default "$1" "$2" \
+		'priority_enable:bool:0' \
+		'priority_netdev:maxlength(8)'
+}
+
 _qosdef_handle_protox() { # <priority> <rule>
 	case "$1" in
 		-400) P1="$P1""$2";;
@@ -61,13 +67,9 @@ qosdef_remove_priority() {
 
 # init traffic priority
 qosdef_init_priority() {
-	local priority_enable priority_netdev ifname="br-lan"
+	local ifname="br-lan"
 
-	uci_validate_section nft-qos default default \
-		'priority_enable:bool:0' \
-		'priority_netdev:maxlength(8)'
-
-	[ $? -ne 0 ] && {
+	[ "$2" = 0 ] || {
 		logger -t nft-qos-priority "validation failed"
 		return 1
 	}