erofs: modify the error message when prepare_ondemand_read failed

When prepare_ondemand_read failed, wrong error message is printed.
The prepare_read is also implemented in cachefiles, so we amend it.
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20240424084247.759432-1-lihongbo22@huawei.comSigned-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

fs/erofs/fscache.c

@@ -151,7 +151,7 @@ static int erofs_fscache_read_io_async(struct fscache_cookie *cookie,
 		if (WARN_ON(len == 0))
 			source = NETFS_INVALID_READ;
 		if (source != NETFS_READ_FROM_CACHE) {
-			erofs_err(NULL, "prepare_read failed (source %d)", source);
+			erofs_err(NULL, "prepare_ondemand_read failed (source %d)", source);
 			return -EIO;
 		}