softap: Use set/getPassphrase to replace set/getWpa2Passphrase

Bug: 142752869
Test: Manual, on/off/setting change for hotspot function
Test: make RunSettingsRoboTests ROBOTEST_FILTER=CodeInspectionTest
Change-Id: I22c89f15a6ef1c5366394431cc5aa7031a573d45

src/com/android/settings/wifi/dpp/WifiDppUtils.java

@@ -349,7 +349,7 @@ public class WifiDppUtils {
         // When the value of this key is read, the actual key is not returned, just a "*".
         // Call privileged system API to obtain actual key.
         final String preSharedKey = removeFirstAndLastDoubleQuotes(
-                softApConfiguration.getWpa2Passphrase());
+                softApConfiguration.getPassphrase());
 
         if (!TextUtils.isEmpty(ssid)) {
             intent.putExtra(EXTRA_WIFI_SSID, ssid);