Modified frequency changed event to framework

Removed the logic to send frequency
changed event to framework, on receiving
WPA_BSS_FREQ_CHANGED_FLAG attribute change.
This is because, this event is specific to
STA side functionality. Added a new frequency
changed notification handler. Send the new
frequency to framework from this handler.

Bug: 233074707
Test: Manual - Established P2P connection & confirmed from logs
      that channel change event is received correctly on
      framework side(used wpa_cli -i<ifname>
      chan_switch 10 2412 0 2412 2412 to trigger channel switch)
Change-Id: I75d3c9ad3ab357ee0d8d9e58bf38870bb3a21e98
diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c
index b724eec..0003d1f 100644
--- a/wpa_supplicant/events.c
+++ b/wpa_supplicant/events.c
@@ -5345,6 +5345,10 @@
 		if (event == EVENT_CH_SWITCH_STARTED)
 			break;
 
+		if (wpa_s->assoc_freq && data->ch_switch.freq &&
+			    (int) wpa_s->assoc_freq != data->ch_switch.freq) {
+			wpas_notify_frequency_changed(wpa_s, data->ch_switch.freq);
+		}
 		wpa_s->assoc_freq = data->ch_switch.freq;
 		wpa_s->current_ssid->frequency = data->ch_switch.freq;
 		if (wpa_s->current_bss &&