log GPU usage on NEOS (#21440)

Co-authored-by: Comma Device <device@comma.ai>

selfdrive/hardware/eon/hardware.py

@@ -379,4 +379,8 @@ class Android(HardwareBase):
     pass
 
   def get_gpu_usage_percent(self):
-    return 0
+    try:
+      used, total = open('/sys/devices/soc/b00000.qcom,kgsl-3d0/kgsl/kgsl-3d0/gpubusy').read().strip().split()
+      return 100.0 * int(used) / int(total)
+    except Exception:
+      return 0