WifiStateMachinePrime: separate softap mode

Split softap mode out from the internal state machine in
WifiStateMachinePrime.  This is the initial step for using dynamic
management for mode managers.

Bug: 31346104
Test: frameworks/opt/net/wifi/tests/wifitests/runtests.sh
Test: manually toggle between modes
Test: wifi integration tests
Change-Id: I0a9a52410d8e9cea58c16b91a2cdd1636ab2f999
3 files changed