uqmi: explicitly disconnect IPv6 address family

Some modems (namely, Telit LE910C4) require the IPv6 connection state to
be cleared explicitly, to avoid reporting "no effect" if IPv6
connection is already connected through autoconnect mechanism, or during
LTE default bearer attach, which would lead to established session, but
without a way to inform protocol handler of the status.

Signed-off-by: Lech Perczak <[email protected]>

package/network/utils/uqmi/files/lib/netifd/proto/qmi.sh

@@ -192,6 +192,7 @@ proto_qmi_setup() {
 
 	# Cleanup current state if any
 	uqmi -s -d "$device" --stop-network 0xffffffff --autoconnect > /dev/null 2>&1
+	uqmi -s -d "$device" --set-ip-family ipv6 --stop-network 0xffffffff --autoconnect > /dev/null 2>&1
 
 	# Go online
 	uqmi -s -d "$device" --set-device-operating-mode online > /dev/null 2>&1