network_config: Leverage a default network file

This will alleviate the need for pre-generating configuration files.
Required for fixing reading of DHCP attributes, as interfaces added by
newer firmware versions will sometimes override old DHCP settings as
they are always read from the first file.

Tested: Ran on a real BMC, cleared the flash. Verified interfaces came
up with default settings and added configurations to the interfaces.

Change-Id: I5fe111be86b59b833d789abdaadee4a43f2e24d3
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meson.build b/meson.build
index d0ac5ce..7b130ec 100644
--- a/meson.build
+++ b/meson.build
@@ -70,6 +70,14 @@
 subdir('src')
 
 configure_file(
+  input: '60-phosphor-networkd-default.network.in',
+  output: '60-phosphor-networkd-default.network',
+  configuration: conf_data,
+  install: true,
+  install_dir: dependency('systemd').get_variable(
+    pkgconfig: 'systemdutildir') / 'network')
+
+configure_file(
   input: 'xyz.openbmc_project.Network.service.in',
   output: 'xyz.openbmc_project.Network.service',
   configuration: {