FEXCore: Add a pre-compilation frontend callback to SyscallHandler

FEXCore/include/FEXCore/HLE/SyscallHandler.h

@@ -76,6 +76,8 @@ public:
   virtual void UnmarkOvercommitRange(uint64_t Start, uint64_t Length) {}
   virtual AOTIRCacheEntryLookupResult LookupAOTIRCacheEntry(FEXCore::Core::InternalThreadState* Thread, uint64_t GuestAddr) = 0;
 
+  virtual void PreCompile() {}
+
   virtual SourcecodeResolver* GetSourcecodeResolver() {
     return nullptr;
   }