Don't run hotspot related tests if Soft AP is not supported

Also explicitly hold ACCESS_WIFI_STATE permission to avoid
no permission problem when using WifiManager#getScanResults
without shell identity.

Fix: 169219565
Test: "atest CtsTetheringTest" in cuttlefish and phyical device

Change-Id: I3d8fa7e8882bf96f61f3316a70efdf991addbcb2
diff --git a/tests/cts/tethering/AndroidManifest.xml b/tests/cts/tethering/AndroidManifest.xml
index 665002e..911dbf2 100644
--- a/tests/cts/tethering/AndroidManifest.xml
+++ b/tests/cts/tethering/AndroidManifest.xml
@@ -19,6 +19,7 @@
     package="android.tethering.cts">
 
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
 
     <application android:debuggable="true">
         <uses-library android:name="android.test.runner" />