NFS: remove sync_mode test from nfs_writepage_locked()

nfs_writepage_locked() is only called from nfs_wb_folio() (since Commit
12fc0a96 ("nfs: Remove writepage")) so ->sync_mode is always
WB_SYNC_ALL.

This means the test for WB_SYNC_NONE is dead code and can be removed.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/write.c

@@ -667,10 +667,6 @@ static int nfs_writepage_locked(struct folio *folio,
 	struct inode *inode = folio_file_mapping(folio)->host;
 	int err;
 
-	if (wbc->sync_mode == WB_SYNC_NONE &&
-	    NFS_SERVER(inode)->write_congested)
-		return AOP_WRITEPAGE_ACTIVATE;
-
 	nfs_inc_stats(inode, NFSIOS_VFSWRITEPAGE);
 	nfs_pageio_init_write(&pgio, inode, 0, false,
 			      &nfs_async_write_completion_ops);