io_uring/notif: raise limit on notification slots

1024 notification slots is rather an arbitrary value, raise it up,
everything is accounted to memcg.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/eb78a0a5f2fa5941f8e845cdae5fb399bf7ba0be.1660566179.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

io_uring/notif.h

@@ -8,7 +8,7 @@
 #include "rsrc.h"
 
 #define IO_NOTIF_SPLICE_BATCH	32
-#define IORING_MAX_NOTIF_SLOTS (1U << 10)
+#define IORING_MAX_NOTIF_SLOTS	(1U << 15)
 
 struct io_notif_data {
 	struct file		*file;