[RDKB][DT][SYNC][OSBNB00182646][MTK_ASK_7.3][RC5]6GHz radio stops beaconing intermittently

[Description]
Fix wifi_getRadioPossibleChannels() HAL API to fetch correct possible channels
for specific country_code DE, US etc.
DE country code has channels possible upto '93' for 6GHz radio,
So channel no > 201 is not vaild for DE.

[Release-log]
N/A

diff --git a/src/logan_wifi/wifi_hal.c b/src/logan_wifi/wifi_hal.c
index 763e5e3..fc3a952 100644
--- a/src/logan_wifi/wifi_hal.c
+++ b/src/logan_wifi/wifi_hal.c
@@ -5487,7 +5487,7 @@
 	if (NULL == output_string)
 		return RETURN_ERR;
 
-	char buf[128] = {0};
+	char buf[256] = {0};
 	BOOL dfs_enable = false;
 	int phyId = 0, res;
 
@@ -5503,8 +5503,8 @@
 	if (res) {
 		wifi_debug(DEBUG_ERROR, "_syscmd_secure fail\n");
 	}
-	strncpy(output_string, buf, strlen(buf) < sizeof(buf) ? strlen(buf) : sizeof(buf));
-
+	strncpy(output_string, buf, strlen(buf));
+	output_string[strlen(buf)]='\0';
 	WIFI_ENTRY_EXIT_DEBUG("Exiting %s:%d\n",__func__, __LINE__);
 	return RETURN_OK;
 }