Fix vfs_procgroup_cleanup not handling hash collisions

kernel/fs/vfs.c

@@ -168,6 +168,8 @@ void vfs_procgroup_cleanup (struct procgroup* procgroup) {
 
   for (size_t i = 0; i < lengthof (mount_table.mountpoint_buckets); i++) {
     struct hash_node_link* link = mount_table.mountpoint_buckets[i];
+
+    while (link != NULL) {
       struct vfs_mountpoint* vmp = hash_entry (link, struct vfs_mountpoint, mount_table_link);
 
       spin_lock (&vmp->lock);
@@ -178,6 +180,9 @@ void vfs_procgroup_cleanup (struct procgroup* procgroup) {
       }
 
       spin_unlock (&vmp->lock);
+
+      link = link->next;
+    }
   }
 
   spin_unlock (&mount_table.lock);