Fix dblist size accounting in the case where ext2fs_resize_mem() fails
to allocate a larger buffer.

Index: e2fsprogs-1.41.10/lib/ext2fs/dblist.c
===================================================================
--- e2fsprogs-1.41.10.orig/lib/ext2fs/dblist.c
+++ e2fsprogs-1.41.10/lib/ext2fs/dblist.c
@@ -169,7 +169,7 @@ errcode_t ext2fs_add_dir_block(ext2_dbli
 					   sizeof(struct ext2_db_entry),
 					   &dblist->list);
 		if (retval) {
-			dblist->size -= 100;
+			dblist->size = old_size / sizeof(struct ext2_db_entry);
 			return retval;
 		}
 	}