WifiManager: Provide getDhcpInfo for secondary STA if applicable

Similar to getConnectionInfo(), provides backwards compatibility for
existing apps using the peer to peer API when STA + STA is enabled.

Bug: 176415610
Test: atest android.net.wifi com.android.server.wifi
Change-Id: I4953696cfd5e9ae7d09a08e1b15cb7d688df40d3
6 files changed