ozone: Switch some DRM-related warnings to VLOG(1).

ui/ozone/platform/drm/gpu/drm_device_manager.cc

Index: ui/ozone/platform/drm/gpu/drm_device_manager.cc
diff --git a/ui/ozone/platform/drm/gpu/drm_device_manager.cc b/ui/ozone/platform/drm/gpu/drm_device_manager.cc
index f520c1478dec60767ea3fed36d739a1ccb5ec732..6b8142bc7df9dc1433379f05dd8d47c3b012c24f 100644
--- a/ui/ozone/platform/drm/gpu/drm_device_manager.cc
+++ b/ui/ozone/platform/drm/gpu/drm_device_manager.cc
@@ -50,7 +50,8 @@ bool DrmDeviceManager::AddDrmDevice(const base::FilePath& path,
   scoped_refptr<DrmDevice> device = drm_device_generator_->CreateDevice(
       path, std::move(file), !primary_device_);
   if (!device) {
-    LOG(WARNING) << "Could not initialize DRM device for " << path.value();
+    // This is expected for non-modesetting devices like VGEM.
+    VLOG(1) << "Could not initialize DRM device for " << path.value();
     return false;
   }