[Wi-Fi] Change material design Wi-Fi signal icon for Wi-Fi Direct

Original icon is also a material design Wi-Fi signal icon but
it's for notification. This one is for devices.

Bug: 134408491
Bug: 139336138
Test: visual
Change-Id: Id14ddbbcede458e2a9f8645d94ecf80d22fe9ab2

src/com/android/settings/wifi/p2p/WifiP2pPeer.java

@@ -58,7 +58,7 @@ public class WifiP2pPeer extends Preference {
         if (mRssi == Integer.MAX_VALUE) {
             mSignal.setImageDrawable(null);
         } else {
-            mSignal.setImageResource(R.drawable.wifi_signal_dark);
+            mSignal.setImageResource(R.drawable.wifi_signal);
             mSignal.setImageState(STATE_SECURED,  true);
         }
         mSignal.setImageLevel(getLevel());