Merge branch 'rs/freebsd-getcwd-workaround'

FreeBSD implementation of getcwd(3) behaved differently when an intermediate directory is unreadable/unsearchable depending on the length of the buffer provided, which our strbuf_getcwd() was not aware of. strbuf_getcwd() has been taught to cope with it better. * rs/freebsd-getcwd-workaround: strbuf: support long paths w/o read rights in strbuf_getcwd() on FreeBSD