openpromfs: remove SLAB_MEM_SPREAD flag usage

The SLAB_MEM_SPREAD flag used to be implemented in SLAB, which was
removed as of v6.8-rc1 (see [1]), so it became a dead flag since the
commit 16a1d96 ("mm/slab: remove mm/slab.c and slab_def.h"). And
the series[1] went on to mark it obsolete explicitly to avoid confusion
for users. Here we can just remove all its users, which has no any
functional change.

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Link: https://lore.kernel.org/all/20240223-slab-cleanup-flags-v2-1-02f1753e8303@suse.cz [1]
Link: https://lore.kernel.org/r/20240224135028.829910-1-chengming.zhou@linux.dev
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: Chengming Zhou

fs/openpromfs/inode.c

@@ -446,7 +446,7 @@ static int __init init_openprom_fs(void)
 					    sizeof(struct op_inode_info),
 					    0,
 					    (SLAB_RECLAIM_ACCOUNT |
-					     SLAB_MEM_SPREAD | SLAB_ACCOUNT),
+					     SLAB_ACCOUNT),
 					    op_inode_init_once);
 	if (!op_inode_cachep)
 		return -ENOMEM;