The sample code here ended up trying to register an eloop socket with fd
== -1. This was not really ever supposed to be used, but it is now also
hitting an assert in eloop. Skip the unnecessary
eloop_register_read_sock() to avoid this.
This was causing issues for hostapd since CONFIG_L2_PACKET is not set by
default. If CONFIG_RSN_PREAUTH=y was not used for CONFIG_L2_PACKET was
not set in .config explicitly, the defaul use of l2_packet_none.c ended
up hitting the newly added assert() in eloop.
Signed-off-by: Jouni Malinen <j@w1.fi>