fixed VDM demo example...

Examples/Theodosius-Kernel/Theodosius-VDM/main.cpp

@@ -190,8 +190,13 @@ int main(int argc, char** argv)
 	};
 
 	theo::hmm_ctx drv_mapper({ _kalloc, _kmemcpy, resolve_symbol });
-	const auto drv_entry = drv_mapper.map_objs(image_objs);
+	if (!drv_mapper.map_objs(image_objs))
+	{
+		std::printf("[!] failed to map object files...\n");
+		return -1;
+	}
 
+	const auto drv_entry = drv_mapper.get_symbol("DrvEntry");
 	std::printf("\n\n> driver entry -> 0x%p\n", drv_entry);
 	std::getchar();