[development] Migrated Atom CPU profiler to utilize new AzCore Profiler interface and related macros (#4160)

- Added new interface type AZ::Debug::Profiler to externally register profiler systems
 - Modified the Atom CPU profiler to register as an AzCore profiler
 -- This allows full engine markers to be visualized in the associated ImGui tool
 - Converted all AZ_ATOM_PROFILE_* macros to use AZ_PROFILE_* macros instead

Signed-off-by: AMZN-ScottR 24445312+AMZN-ScottR@users.noreply.github.com

Code/Framework/AzCore/AzCore/Debug/Profiler.h

@@ -59,6 +59,20 @@ namespace AZStd
 
 namespace AZ::Debug
 {
+    // interface for externally defined profiler systems
+    class Profiler
+    {
+    public:
+        AZ_RTTI(Profiler, "{3E5D6329-72D1-41BA-9158-68A349D1A4D5}");
+
+        Profiler() = default;
+        virtual ~Profiler() = default;
+
+        // support for the extra macro args (e.g. format strings) will come in a later PR
+        virtual void BeginRegion(const Budget* budget, const char* eventName) = 0;
+        virtual void EndRegion(const Budget* budget) = 0;
+    };
+
     class ProfileScope
     {
     public:

Code/Framework/AzCore/AzCore/Debug/Profiler.inl

@@ -6,6 +6,8 @@
  *
  */
 
+#include <AzCore/Interface/Interface.h>
+
 namespace AZ::Debug
 {
     template<typename... T>
@@ -22,9 +24,11 @@ namespace AZ::Debug
         PIXBeginEvent(PIX_COLOR_INDEX(budget->Crc() & 0xff), eventName, args...);
 #endif
         budget->BeginProfileRegion();
-// TODO: injecting instrumentation for other profilers
-// NOTE: external profiler registration won't occur inline in a header necessarily in this manner, but the exact mechanism
-//       will be introduced in a future PR
+
+        if (auto profiler = AZ::Interface<Profiler>::Get(); profiler)
+        {
+            profiler->BeginRegion(budget, eventName);
+        }
 #endif
     }
 
@@ -39,6 +43,10 @@ namespace AZ::Debug
 #if defined(USE_PIX)
         PIXEndEvent();
 #endif
+        if (auto profiler = AZ::Interface<Profiler>::Get(); profiler)
+        {
+            profiler->EndRegion(budget);
+        }
 #endif
     }