Revert "[Bugfix][API-959][T800]fix when stop sta,wlan0 didn't free ip"

This reverts commit feb0a7ed4a0e646030cc2dbc004fbcf06cd49150.

Reason for revert: <INSERT REASONING HERE>

Change-Id: I39761103c8085ae73f042d4583dfb80b02f76f4b
diff --git a/src/lynq/lib/liblynq-wifi6/libwifi6.c b/src/lynq/lib/liblynq-wifi6/libwifi6.c
index 6323852..e6c394b 100755
--- a/src/lynq/lib/liblynq-wifi6/libwifi6.c
+++ b/src/lynq/lib/liblynq-wifi6/libwifi6.c
@@ -2869,15 +2869,8 @@
 
     system("connmanctl enable wifi");
 
-    if (system("ifconfig wlan0 up") != 0)
-    {
-        RLOGE("ifconfig wlan0 up fail\n");
-        return -1;
-    }
-
     if (system("ifconfig | grep -q wlan0") != 0)
     {
-        RLOGE("check wlan0 up fail\n");
         return -1;
     }
 
@@ -2913,12 +2906,6 @@
     system(lynq_disable_sta_cmd);
     DO_OK_FAIL_REQUEST(cmd_save_config);
 
-    if (system("ifconfig wlan0 down") != 0)
-    {
-        RLOGD("ifconfig wlan0 down fail\n");
-        return -1;
-    }
-
     return 0;
 //    return system("connmanctl disable wifi");
 }