[misc] feat: add B200 and GB200 flops count (volcengine#3041)

### What does this PR do?

- add B200 and GB200 flops count

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Author: vermouth1992

verl/utils/flops_counter.py

@@ -70,6 +70,10 @@ def unit_convert(number, level):
     if "CPU" in device_name:
         # use a general CPU flops placeholder to make the function CPU compatible
         flops = 448e9
+    elif "GB200" in device_name:
+        flops = 2.5e15
+    elif "B200" in device_name:
+        flops = 2.25e15
     elif "MI300X" in device_name:
         flops = 1336e12
     elif "H100" in device_name or "H800" in device_name or "H200" in device_name: