oniro-linux-blueprint-gateway: Disable dnsmasq service by default

In our core distributions we disable the dnsmaq packageconfig for
networkmanager. Re-enable it here as we need it for the Soft AP use
case.
If dnsmasq runs as active systemd service by default it conflicts with
network-manager which calls it directly. For this blueprint we want to
leave the control in networkmanagers realm.

Signed-off-by: Stefan Schmidt <stefan.schmidt@huawei.com>

meta-oniro-blueprints/conf/distro/oniro-linux-blueprint-gateway.conf

@@ -31,3 +31,11 @@ ST_USERFS = "0"
 # mask out the blueprint layers in the main distro and unmask
 # them only the blueprint distributions.
 BBMASK = ""
+
+# If dnsmaq runs as system service started by systemd it clashes with NM, which
+# directly calls it.
+SYSTEMD_AUTO_ENABLE_pn-dnsmasq = "disable"
+
+# We have the dnsmasq feature disabled for networkmanager in core,
+# but we need this for the gateway. Enable it for the blueprint only.
+PACKAGECONFIG_append_pn-networkmanager = " dnsmasq"