fix build warnings

app/src/main/java/com/geeksville/mesh/MainActivity.kt

@@ -353,14 +353,14 @@ class MainActivity : AppCompatActivity(), Logging,
     private val mesh = object : ServiceClient<com.geeksville.mesh.IMeshService>({
         com.geeksville.mesh.IMeshService.Stub.asInterface(it)
     }) {
-        override fun onConnected(m: com.geeksville.mesh.IMeshService) {
-            UIState.meshService = m
+        override fun onConnected(service: com.geeksville.mesh.IMeshService) {
+            UIState.meshService = service
 
             // We don't start listening for packets until after we are connected to the service
             registerMeshReceiver()
 
             // We won't receive a notify for the initial state of connection, so we force an update here
-            onMeshConnectionChanged(m.isConnected)
+            onMeshConnectionChanged(service.isConnected)
 
             debug("connected to mesh service, isConnected=${UIState.isConnected.value}")
         }

app/src/main/java/com/geeksville/mesh/service/MeshService.kt

@@ -557,7 +557,7 @@ class MeshService : Service(), Logging {
 
         // FIXME, perhaps we could learn our node ID by looking at any to packets the radio
         // decided to pass through to us (except for broadcast packets)
-        val toNum = packet.to
+        //val toNum = packet.to
 
         val p = packet.payload
 

app/src/main/java/com/geeksville/mesh/ui/Settings.kt

@@ -56,7 +56,6 @@ fun SettingsContent() {
         if (!bonded) {
 
             val typography = MaterialTheme.typography()
-            val context = ambient(ContextAmbient)
 
             Text(
                 text =