report fb_queue error in fuse_lookup to simplify debugging [tiny patch]

[IL Ka]

There are some people on @misc faced with
"libfuse vnode reclaim failed" error.

http://openbsd-archive.7691.n7.nabble.com/sshfuse-fusefs-libfuse-vnode-reclaim-failed-td341072.html

I suggest to report errno explicitly so, people
will be able to use intro(2) to find description of error


diff --git sys/miscfs/fuse/fuse_lookup.c sys/miscfs/fuse/fuse_lookup.c
index 5ccc9fe81..a3c57abdf 100644
--- sys/miscfs/fuse/fuse_lookup.c
+++ sys/miscfs/fuse/fuse_lookup.c
@@ -196,8 +196,10 @@ fusefs_lookup(void *v)
 reclaim:
        if (nid != dp->ufs_ino.i_number && nid != FUSE_ROOTINO) {
                fbuf = fb_setup(0, nid, FBT_RECLAIM, p);
-               if (fb_queue(fmp->dev, fbuf))
-                       printf("fusefs: libfuse vnode reclaim failed\n");
+               int queue_error;
+               queue_error = fb_queue(fmp->dev, fbuf);
+               if (queue_error != 0)
+                       printf("fusefs: libfuse vnode reclaim failed:
%d\n", queue_error);
                fb_delete(fbuf);
        }
        return (error);