Remove unused INetworkManagementService from IpSecService

IpSecService is no longer using any methods of
INetworkManagementService, so remove it from IpSecService
and related files.

Bug: 170598012
Test: atest FrameworksNetTests
Change-Id: I852e3a534e0ffd26b4b22420754f3ec8a6f153ad

services/java/com/android/server/SystemServer.java

@@ -1532,7 +1532,7 @@ public final class SystemServer {
 
             t.traceBegin("StartIpSecService");
             try {
-                ipSecService = IpSecService.create(context, networkManagement);
+                ipSecService = IpSecService.create(context);
                 ServiceManager.addService(Context.IPSEC_SERVICE, ipSecService);
             } catch (Throwable e) {
                 reportWtf("starting IpSec Service", e);