Implement getInterfaceHash/Version (USB)

As these interfaces get frozen, java services
implementing the interfaces are required to implement getInterfaceHash
and getInterfaceVersion [1]

[1]
https://source.android.com/devices/architecture/aidl/stable-aidl#new-meta-interface-methods

Bug: 190577319
Test: m
Change-Id: I00ced32a26fd1af7bc8cc23749d92ae90d5a5a0f

services/usb/java/com/android/server/usb/hal/port/UsbPortAidl.java

@@ -725,5 +725,15 @@ public final class UsbPortAidl implements UsbPortHal {
                         e);
             }
         }
+
+        @Override
+        public String getInterfaceHash() {
+            return IUsbCallback.HASH;
+        }
+
+        @Override
+        public int getInterfaceVersion() {
+            return IUsbCallback.VERSION;
+        }
     }
 }