net: wifi: Add reasons for 4 way handshake failure

When there is 4 way handshake timeout, it can be because of
incorrect credential or some times when AP's signal strength
is weak. It can cause 4 way handshake fail. Adding comment
where WIFI_STATUS_CONN_WRONG_PASSWORD is defined.

Signed-off-by: Kapil Bhatt <kapil.bhatt@nordicsemi.no>