eventfd: change int to __u64 in eventfd_signal() ifndef CONFIG_EVENTFD

Commit ee62c6b2 ("eventfd: change int to __u64 in eventfd_signal()")
forgot to change int to __u64 in the CONFIG_EVENTFD=n stub function.

Link: https://lkml.kernel.org/r/20221124140154.104680-1-zhangqilong3@huawei.com
Fixes: ee62c6b2 ("eventfd: change int to __u64 in eventfd_signal()")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Cc: Dylan Yudaken <dylany@fb.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Sha Zhengju <handai.szj@taobao.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/eventfd.h

@@ -61,7 +61,7 @@ static inline struct eventfd_ctx *eventfd_ctx_fdget(int fd)
 	return ERR_PTR(-ENOSYS);
 }
 
-static inline int eventfd_signal(struct eventfd_ctx *ctx, int n)
+static inline int eventfd_signal(struct eventfd_ctx *ctx, __u64 n)
 {
 	return -ENOSYS;
 }