wifi(API): Mark old API's deprecated

List of API's that are obsoleted by the new connection API proposed for
Q. These API's will continue to work with some restrictions for apps
targeting older SDK.
Also, removes the ability for 3p apps to toggle wifi state regardless of
target SDK. This will be limited to 1p apps like settings/setup wizard.

Bug: 115504728
Test: Compiles
Change-Id: Ifec5ab721b37bc334ff7448b7829df4be2dcab37