Ignore unused benchmark state variables

Signed-off-by: Chris Burel <burelc@amazon.com>

Code/Framework/AzCore/Tests/DOM/DomPatchBenchmarks.cpp

@@ -78,7 +78,7 @@ namespace AZ::Dom::Benchmark
             if (apply)
             {
                 auto patchInfo = GenerateHierarchicalDeltaPatch(m_before, m_after);
-                for (auto _ : state)
+                for ([[maybe_unused]] auto _ : state)
                 {
                     auto patchResult = patchInfo.m_forwardPatches.Apply(m_before);
                     benchmark::DoNotOptimize(patchResult);
@@ -86,7 +86,7 @@ namespace AZ::Dom::Benchmark
             }
             else
             {
-                for (auto _ : state)
+                for ([[maybe_unused]] auto _ : state)
                 {
                     auto patchInfo = GenerateHierarchicalDeltaPatch(m_before, m_after);
                     benchmark::DoNotOptimize(patchInfo);

Code/Framework/AzCore/Tests/DOM/DomPathBenchmarks.cpp

@@ -104,7 +104,7 @@ namespace AZ::Dom::Benchmark
         PathEntry endOfArray;
         endOfArray.SetEndOfArray();
 
-        for (auto _ : state)
+        for ([[maybe_unused]] auto _ : state)
         {
             benchmark::DoNotOptimize(name == name);
             benchmark::DoNotOptimize(name == index);

Gems/SurfaceData/Code/Tests/SurfaceDataBenchmarks.cpp

@@ -289,7 +289,7 @@ namespace UnitTest
             tag = randomGenerator.GetRandom();
         }
 
-        for (auto _ : state)
+        for ([[maybe_unused]] auto _ : state)
         {
             // We'll benchmark this two ways:
             // 1. We clear each time, which means each AddSurfaceWeightIfGreater call will search the whole list then add.
@@ -340,7 +340,7 @@ namespace UnitTest
             comparisonTags.emplace_back(tag ^ 0x01);
         }
 
-        for (auto _ : state)
+        for ([[maybe_unused]] auto _ : state)
         {
             // Test to see if any of our tags match.
             // All of comparison tags should get compared against all of the added tags.