Revert "Unhide IpPrefix(InetAddress, int)" am: 758ead6dd3 am: ea0caefdd2 am: 6c75679f1d

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1927303

Change-Id: I2c5800b1850917dcf573e0456b80734b847689c2