Added Metal comment info

Author: eduardodoria

engine/renders/sokol/SokolObject.cpp

@@ -124,6 +124,7 @@ void SokolObject::addAttribute(int slotAttribute, BufferRender* buffer, unsigned
 
  // D3D11 cannot have offset (AlignedByteOffset) bigger than 2048
  // https://github.com/floooh/sokol/issues/818
+ // Metal also cannot use large offsets
  size_t bufferOffset = 0;
  size_t attrOffset = 0;