[PATCH] Handle the errors from chdir in set_work_tree

These I haven't seen yet. Wouldn't like such a surprise though.
Also unstatic rel, it seems to be declared static accidentally.

Signed-off-by: Alex Riesen <redacted>
---

One gets paranoid when exposed to "commercial"
systems for too long.

 setup.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)