Remove unnecessary NULL check from LOG_LEVEL handler

cmd cannot be NULL here, so there is no need to check it before calling
os_strlen().

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

hostapd/ctrl_iface.c

@@ -1992,7 +1992,7 @@ static int hostapd_ctrl_iface_log_level(struct hostapd_data *hapd, char *cmd,
 		}
 	}
 
-	if (cmd && os_strlen(cmd)) {
+	if (os_strlen(cmd)) {
 		int level = str_to_debug_level(cmd);
 		if (level < 0)
 			return -1;

wpa_supplicant/ctrl_iface.c

@@ -2168,7 +2168,7 @@ static int wpa_supplicant_ctrl_iface_log_level(struct wpa_supplicant *wpa_s,
 		}
 	}
 
-	if (cmd && os_strlen(cmd)) {
+	if (os_strlen(cmd)) {
 		int level = str_to_debug_level(cmd);
 		if (level < 0)
 			return -1;