Fixed code setting anonymous_identity to anonymous@<realm>

Need to set anonymous@<realm> in enterprise config before
saving WifiConfiguration to WifiConfigManager.

Bug: 133431451
Test: frameworks/opt/net/wifi/tests/wifitests/runtests.sh
Test: Manual

Change-Id: I2dcf85e6fdabd98fc15dc946ddf30a3d95297016
6 files changed