Make proactive key caching working again

Make proactive key caching working again

Function 'wpa_sm_set_config' used the argument 'config' as the network
context which is a pointer to a local variable of the function
'wpa_supplicant_rsn_supp_set_config'.

This is one reason why no proactive key was generated. This network
context never matched with the network context saved in the pmksa cache
entries.

The structure 'rsn_supp_config' has already a member 'network_ctx' which
is now filled in by this patch with 'ssid'.

Signed-off-by: Michael Bernhard <michael.bernhard@bfh.ch>