EAP-pwd: Document group configuration for hostapd authentication server

hostapd/hostapd.conf

@@ -510,6 +510,10 @@ eap_server=0
 # Fragment size for EAP methods
 #fragment_size=1400
 
+# Finite cyclic group for EAP-pwd. Number maps to group of domain parameters
+# using the IANA repository for IKE (RFC 2409).
+#pwd_group=19
+
 # Configuration data for EAP-SIM database/authentication gateway interface.
 # This is a text string in implementation specific format. The example
 # implementation in eap_sim_db.c uses this as the UNIX domain socket name for