Add error for NTP server property

It is observed that on passing invalid arguments to configure NTP
servers phosphor-netword is crashing because it is not throwing the
invalid argument exception

To address the issue adding error invalid argument as it is not
present currently. The MRs created for returning invalid argument are
below

https://gerrit.openbmc.org/c/openbmc/phosphor-networkd/+/82694 and
https://gerrit.openbmc.org/c/openbmc/bmcweb/+/82696

Change-Id: Iebd09b482d0938c614d87e9cbd8fa1b765e0309a
Signed-off-by: Chandramohan Harkude <chandramohan.harkude@gmail.com>
diff --git a/yaml/xyz/openbmc_project/Network/EthernetInterface.interface.yaml b/yaml/xyz/openbmc_project/Network/EthernetInterface.interface.yaml
index 5bbb6fd..4016cb4 100644
--- a/yaml/xyz/openbmc_project/Network/EthernetInterface.interface.yaml
+++ b/yaml/xyz/openbmc_project/Network/EthernetInterface.interface.yaml
@@ -72,6 +72,8 @@
           This property describes statically defined NTPServers on the
           interface. This property supports read/write operation. Configure the
           NTP servers on the system during write operation.
+      errors:
+          - xyz.openbmc_project.Common.Error.InvalidArgument
     - name: LinkLocalAutoConf
       type: enum[self.LinkLocalConf]
       description: >