[CI/Build] Resolve hardware-nested perf baselines per concurrency sweep (#5845)

Signed-off-by: wangyu <410167048@qq.com>
Signed-off-by: [Your Name] <your.email@example.com>
Co-authored-by: amy-why-3459 <wuhaiyan17@huawei.com>

tests/dfx/perf/scripts/result_omni_template.json

@@ -46,9 +46,11 @@
   "median_audio_duration_s": 0,
   "p99_audio_duration_s": 0,
   "baseline": {
-    "mean_ttft_ms": 0,
-    "mean_audio_ttfp_ms": 0,
-    "mean_audio_rtf": 0
+    "H100": {
+      "mean_ttft_ms": 0,
+      "mean_audio_ttfp_ms": 0,
+      "mean_audio_rtf": 0
+    }
   },
   "random_input_len": 0,
   "random_output_len": 0