tree: fix incorrect return value

nvme_scan_subsystem() accidentally sets errno = -EINVAL
if the matching subsystem is filtered out.
This errno value will be overwritten by the out_free path with -ret,
where ret is the length of the path string.
Set ret = -EINVAL instead, so errno will be set to EINVAL.
This matches the behavior in the case where a new subsystem is allocated
and fails the filter function.

Signed-off-by: Caleb Sander <[email protected]>

Author: calebsander

src/nvme/tree.c

@@ -725,7 +725,7 @@ static int nvme_scan_subsystem(struct nvme_root *r, const char *name,
 			if (strcmp(_s->name, name))
 				continue;
 			if (!__nvme_scan_subsystem(r, _s, f, f_args)) {
-				errno = -EINVAL;
+				ret = -EINVAL;
 				goto out_free;
 			}
 			s = _s;