wifi: Move Wi-Fi enterprise configs to a snippet

Instead of having an overlay move the Enterprise configurations to a
dedicated snippet so that it can be enabled with any sample.

Can be used along with Wi-Fi snippet e.g., `-S
"wifi-ipv4;wifi-enterprise"`.

Signed-off-by: Chaitanya Tata <Chaitanya.Tata@nordicsemi.no>
5 files changed