bcachefs: Fix btree node prefetchig

We were forgetting to count down the number of nodes to prefetch, firing
off _way_ more than intended - whoops.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2022-10-14 07:20:05 -04:00
commit dccedaaa52