Wifi: DPP STA Enrollee-Responder mode

Added system APIs for DPP STA Enrollee-Responder mode
 - start DPP in Enrollee-Responder mode
 - Callback function to pass Generated DPP bootstrap URI
Defined a new failure code to indicate generate DPP
URI failure.

Bug: 162686712
Test: atest 8BFAZ01446 com.android.server.wifi
Test: act.py -c <dpp config file> -tc WifiDppTest
Change-Id: I094d06dd1f195aa9d647deb65cca91a81cfc10db