In Atom_Feature_Common.static, get cvar values from cvar system instead of reading directly (#5350)

Signed-off-by: Tommy Walton <waltont@amazon.com>

Gems/Atom/Feature/Common/Code/Source/FrameCaptureSystemComponent.cpp

@@ -97,7 +97,12 @@ namespace AZ
             Utils::PngFile image = Utils::PngFile::Create(readbackResult.m_imageDescriptor.m_size, format, *buffer);
 
             Utils::PngFile::SaveSettings saveSettings;
-            saveSettings.m_compressionLevel = r_pngCompressionLevel;
+
+            if (auto console = AZ::Interface<AZ::IConsole>::Get(); console != nullptr)
+            {
+                console->GetCvarValue("r_pngCompressionLevel", saveSettings.m_compressionLevel);
+            }
+
             // We should probably strip alpha to save space, especially for automated test screenshots. Alpha is left in to maintain
             // prior behavior, changing this is out of scope for the current task. Note, it would have bit of a cascade effect where
             // AtomSampleViewer's ScriptReporter assumes an RGBA image.

Gems/Atom/Feature/Common/Code/Source/SkinnedMesh/SkinnedMeshOutputStreamManager.cpp

@@ -98,7 +98,12 @@ namespace AZ
             }
             m_needsInit = false;
 
-            const AZ::u64 sizeInMb = r_skinnedMeshInstanceMemoryPoolSize;
+            AZ::u64 sizeInMb{};
+            if (auto console = AZ::Interface<AZ::IConsole>::Get(); console != nullptr)
+            {
+                console->GetCvarValue("r_skinnedMeshInstanceMemoryPoolSize", sizeInMb);
+            }
+
             m_sizeInBytes = sizeInMb * (1024u * 1024u);
 
             CalculateAlignment();