Fix rpc devices getting lost after scan if devices did not change.

src/main/java/li/cil/oc2/common/bus/RPCAdapter.java

@@ -87,9 +87,6 @@ public final class RPCAdapter implements Steppable {
         pauseLock.lock();
         isPaused = true;
         pauseLock.unlock();
-
-        devices.clear();
-        devicesById.clear();
     }
 
     public void resume(final boolean didDevicesChange) {
@@ -99,6 +96,9 @@ public final class RPCAdapter implements Steppable {
             return;
         }
 
+        devices.clear();
+        devicesById.clear();
+
         // How device grouping works:
         // Each device can have multiple UUIDs due to being attached to multiple bus elements.
         // There is no guarantee that for each device D1 present on bus elements E1 and E2,