WifiConfiguration: Remove priority field

This field is no longer used anywhere within wifi framework and hence
removing this from public API.

Bug: 28341078
Test: make update-api
Change-Id: I5bd115742ca610735b00c20f2ffab7590c5f3256

api/current.txt

@@ -24632,7 +24632,7 @@ package android.net.wifi {
     field public boolean isHomeProviderNetwork;
     field public int networkId;
     field public java.lang.String preSharedKey;
-    field public int priority;
+    field public deprecated int priority;
     field public java.lang.String providerFriendlyName;
     field public long[] roamingConsortiumIds;
     field public int status;

api/system-current.txt

@@ -26988,7 +26988,7 @@ package android.net.wifi {
     field public int numScorerOverride;
     field public int numScorerOverrideAndSwitchedNetwork;
     field public java.lang.String preSharedKey;
-    field public int priority;
+    field public deprecated int priority;
     field public java.lang.String providerFriendlyName;
     field public long[] roamingConsortiumIds;
     field public int status;

api/test-current.txt

@@ -24705,7 +24705,7 @@ package android.net.wifi {
     field public boolean isHomeProviderNetwork;
     field public int networkId;
     field public java.lang.String preSharedKey;
-    field public int priority;
+    field public deprecated int priority;
     field public java.lang.String providerFriendlyName;
     field public long[] roamingConsortiumIds;
     field public int status;

wifi/java/android/net/wifi/WifiConfiguration.java

@@ -305,7 +305,9 @@ public class WifiConfiguration implements Parcelable {
     /**
      * Priority determines the preference given to a network by {@code wpa_supplicant}
      * when choosing an access point with which to associate.
+     * @deprecated Priority is no longer used.
      */
+    @Deprecated
     public int priority;
 
     /**