bcachefs: Minor bch2_btree_node_get() smatch fixes

- it's no longer possible for trans to be NULL
 - also, move "wait for read to complete" to the slowpath,
   __bch2_btree_node_get().

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2023-09-20 01:31:00 -04:00
commit 51c801bc64