[CI] Add arch prefix in front of op benchmark results (#165584)

To be able to run x86 and aarch64 benchmarks later on
Pull Request resolved: https://github.com/pytorch/pytorch/pull/165584
Approved by: https://github.com/huydhn
ghstack dependencies: #165583

.ci/pytorch/test.sh

@@ -1615,6 +1615,7 @@ test_operator_benchmark() {
   TEST_REPORTS_DIR=$(pwd)/test/test-reports
   mkdir -p "$TEST_REPORTS_DIR"
   TEST_DIR=$(pwd)
+  ARCH=$(uname -m)
 
   test_inductor_set_cpu_affinity
 
@@ -1629,7 +1630,7 @@ test_operator_benchmark() {
   pip_install pandas
   python check_perf_csv.py \
       --actual "${TEST_REPORTS_DIR}/operator_benchmark_eager_float32_cpu.csv" \
-      --expected "expected_ci_operator_benchmark_eager_float32_cpu.csv"
+      --expected "${ARCH}_expected_ci_operator_benchmark_eager_float32_cpu.csv"
 }
 
 test_operator_microbenchmark() {

.github/workflows/operator_benchmark.yml

@@ -30,9 +30,9 @@ permissions:
   contents: read
 
 jobs:
-  opbenchmark-build:
+  x86-opbenchmark-build:
     if: github.repository_owner == 'pytorch'
-    name: opbenchmark-build
+    name: x86-opbenchmark-build
     uses: ./.github/workflows/_linux-build.yml
     with:
       build-environment: linux-jammy-py3.10-gcc11-build
@@ -43,12 +43,12 @@ jobs:
         ]}
     secrets: inherit
 
-  opbenchmark-test:
-    name: opbenchmark-test
+  x86-opbenchmark-test:
+    name: x86-opbenchmark-test
     uses: ./.github/workflows/_linux-test.yml
-    needs: opbenchmark-build
+    needs: x86-opbenchmark-build
     with:
       build-environment: linux-jammy-py3.10-gcc11-build
-      docker-image: ${{ needs.opbenchmark-build.outputs.docker-image }}
-      test-matrix: ${{ needs.opbenchmark-build.outputs.test-matrix }}
+      docker-image: ${{ needs.x86-opbenchmark-build.outputs.docker-image }}
+      test-matrix: ${{ needs.x86-opbenchmark-build.outputs.test-matrix }}
     secrets: inherit