[nrf fromtree] wifi: utils: Fix crash for scan

The check for index out of bound is missing, It turns into a crash
for input channel more than WIFI_MGMT_SCAN_CHAN_MAX_MANUAL.

Signed-off-by: Kapil Bhatt <[email protected]>
(cherry picked from commit 6f9dbbd)

Author: kapbh

subsys/net/l2/wifi/wifi_utils.c

@@ -175,6 +175,10 @@ static int wifi_utils_get_all_chans_in_range(uint8_t chan_start,
 			}
 
 			if (start) {
+				if (idx > WIFI_MGMT_SCAN_CHAN_MAX_MANUAL) {
+					*chan_idx = idx;
+					break;
+				}
 				band_chan[idx].band = band_idx;
 				band_chan[idx].channel = valid_5g_chans_20mhz[i];
 				idx++;