ethernet_interface: Remove optional signal emission

We don't ever need to turn this off anymore, so we can simplify creation
arguments.

Change-Id: Idb1bde35041f16d409753ff661bfb248cfd4591e
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/src/network_manager.cpp b/src/network_manager.cpp
index 99bedaa..82eb2c5 100644
--- a/src/network_manager.cpp
+++ b/src/network_manager.cpp
@@ -141,7 +141,7 @@
     }
     config::Parser config(config::pathForIntfConf(confDir, *info.intf.name));
     auto intf = std::make_unique<EthernetInterface>(
-        bus, *this, info.intf, objPath.str, config, true, enabled);
+        bus, *this, info.intf, objPath.str, config, enabled);
     if (info.defgw4)
     {
         intf->EthernetInterface::defaultGateway(std::to_string(*info.defgw4));