wifi: correct API name

The API:isFeatureSupported accept one or combination
of required features, update the jave doc & rename to areFeaturesSupporte

Bug: 149871866
Test: make docs frameworks/base/wifi/
Test: atest frameworks/base/wifi/tests/
Change-Id: I3bcbcfd04dced36b63436b5a96835fb0d8f35f3b
3 files changed