Remove UgBgGroupThrottle node to keep ug_bg_group_throttle 308 by default

Bug: 280258727
Test: Found regression in b/286002292, local test.
Change-Id: Ief3d1bded3add877b23b4c2b211cef6d5a9eaf57
Signed-off-by: paulsu <[email protected]>

powerhint.json

@@ -613,16 +613,6 @@
       ],
       "DefaultIndex": 0,
       "ResetOnInit": true
-    },
-    {
-      "Name": "UgBgGroupThrottle",
-      "Path": "/proc/vendor_sched/ug_bg_group_throttle",
-      "Values": [
-        "512",
-        "308"
-      ],
-      "DefaultIndex": 0,
-      "ResetOnInit": true
     }
   ],
   "Actions": [