Fix DataTargetReader::AlignBase() (#28072)

DAC_ALIGNAS macro was used to force MSVC and clang/gcc
compilers layouts to match.  Update DataTargetReader::AlignBase()
assumptions based on new layouts

src/md/datasource/datatargetreader.cpp

@@ -163,13 +163,10 @@ void DataTargetReader::Align(DWORD alignmentBytes)
 
 void DataTargetReader::AlignBase()
 {
-#ifdef _MSC_VER
-    // Windows MSVC compiler aligns structs based on the largest field size
+    // Align structs based on the largest field size
+    // This is the default for MSVC compilers
+    // This is forced on other platforms by the DAC_ALIGNAS macro
     Align(m_currentStructureAlign);
-#else
-    // clang (on all platforms) aligns structs always on 4 byte boundaries
-    Align(4);
-#endif
 }
 
 HRESULT DataTargetReader::GetRemotePointerSize(ULONG32* pPointerSize)