Common code doesn't test the error flag, so we don't need to set it in
bcachefs.  We can use folio_end_read() to combine the setting (or not)
of the uptodate flag and clearing the lock flag.

Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Brian Foster <bfoster@redhat.com>
Cc: linux-bcachefs@vger.kernel.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>