wpa_supplicant core change to support 11b only mode

Detect 11b modes in association req/resp frames.

Bug: 163912712
Test: atest VtsHalWifiSupplicantV1_0TargetTest \
            VtsHalWifiSupplicantV1_1TargetTest \
	    VtsHalWifiSupplicantV1_2TargetTest \
	    VtsHalWifiSupplicantV1_3TargetTest \
	    VtsHalWifiSupplicantV1_4TargetTest
Test: manual test with 11b only AP to confirm 11b mode is detected and
passed to throughput predictor correctly.

Change-Id: I259efa09edf67a46990b52de290ee66dff627b66
diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c
index e2cae4b..d08deb4 100644
--- a/wpa_supplicant/events.c
+++ b/wpa_supplicant/events.c
@@ -2621,6 +2621,8 @@
 					   data->assoc_info.resp_ies_len,
 					   &resp_elems, 0) != ParseFailed) {
 			wpa_s->connection_set = 1;
+			wpa_s->connection_11b_only = supp_rates_11b_only(&req_elems) ||
+				supp_rates_11b_only(&resp_elems);
 			wpa_s->connection_ht = req_elems.ht_capabilities &&
 				resp_elems.ht_capabilities;
 			/* Do not include subset of VHT on 2.4 GHz vendor