Disable expanded udfps overlay in enrollment when using talkback

When talkback is enabled during enrollment, the udfps overlay will use the sensor size instead of the expanded overlay bounds (bottom half of screen). Prevents the issue of intercepting touches during enrollment and fixes talback bounds being drawn incorrectly.

Change-Id: Iea4189efe5c060a158e52b838aede900993b744e
Bug: 270437012
Test: atest SystemUITests:com.android.systemui.biometrics