Revert "app-emulation/wa-linux-agent: Disable interface restarting"

This reverts commit 9556c7f94b
because waagent looks for internal hostname changes and wants to
propagate them to the Azure VM properties by issuing a new DHCP request.

sdk_container/src/third_party/coreos-overlay/app-emulation/wa-linux-agent/files/0001-flatcar-changes.patch

@@ -172,7 +172,7 @@ new file mode 100644
 index 00000000..e31b2923
 --- /dev/null
 +++ b/azurelinuxagent/common/osutil/flatcar.py
-@@ -0,0 +1,80 @@
+@@ -0,0 +1,78 @@
 +#
 +# Copyright 2023 Microsoft Corporation
 +#
@@ -240,8 +240,6 @@ index 00000000..e31b2923
 +        Restart an interface by bouncing the link. systemd-networkd observes
 +        this event, and forces a renew of DHCP.
 +        """
-+        logger.info("not restarting interface {}".format(ifname))
-+        return
 +        retry_limit = retries + 1
 +        for attempt in range(1, retry_limit):
 +            return_code = shellutil.run("ip link set {0} down && ip link set {0} up".format(ifname))