packagefs: Acquire some more write locks to fix assertion failures.

src/add-ons/kernel/file_systems/packagefs/kernel_interface.cpp

@@ -94,6 +94,7 @@ packagefs_unmount(fs_volume* fsVolume)
 
 	FUNCTION("volume: %p\n", volume);
 
+	volume->WriteLock();
 	volume->Unmount();
 	delete volume;
 

src/add-ons/kernel/file_systems/packagefs/volume/Volume.cpp

@@ -1775,6 +1775,8 @@ Volume::_CreateShineThroughDirectories(const char* shineThroughSetting)
 status_t
 Volume::_PublishShineThroughDirectories()
 {
+	NodeWriteLocker rootDirectoryWriteLocker(fRootDirectory);
+
 	// Iterate through the root directory children and bind the shine-through
 	// directories to the respective mount point subdirectories.
 	Node* nextNode;