networkmanager: Change PACKAGECONFIG to a direct assignment

Having the PACKAGECONFIG_remove in an bbappend file makes it really hard
to consume this layer and bring the specific config back with an _append
(happens for me with the gateway blueprint.

Instead we are now making a direct assignment, with he values removed
taken into account, from our distro as policy. This allows other distros
or layers consuming meta-oniro-core to change it as needed.

A new oniro-packageconfig.inc include file is created in which we will
consolidate other PACKAGECONFIG changes in the next commit.

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

meta-oniro-core/conf/distro/include/oniro-packageconfig.inc

+# SPDX-FileCopyrightText: Huawei Inc.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+# Define the configuration set as per our distro policy
+PACKAGECONFIG_pn-networkmanager = "nss systemd bluez5 wifi"

meta-oniro-core/conf/distro/oniro-linux.conf

@@ -90,6 +90,7 @@ BB_HASHSERVE ??= "auto"
 
 require conf/distro/include/oniro.inc
 require conf/distro/include/oniro-wic.inc
+require conf/distro/include/oniro-packageconfig.inc
 
 TCLIBC ?= "musl"
 

meta-oniro-core/recipes-connectivity/networkmanager/networkmanager_%.bbappend

@@ -6,5 +6,3 @@ inherit writables
 
 WRITABLES = "system-connections"
 WRITABLE_PATH[system-connections] = "/etc/NetworkManager/system-connections"
-
-PACKAGECONFIG_remove = "dhclient dnsmasq ifupdown"