Since 3c610df550 this resulted in `getting status of`
errors on paths inside the chroot if a path was already valid. Careful inspection
of the logic shows that if buildMode != bmCheck actualPath gets reassigned to
store.toRealPath(finalDestPath). The only branch that cares about actualPath is
the buildMode == bmCheck case, which doesn't lead to optimisePath anyway.
(cherry picked from commit 4cbcaad435)
dadb5b01b7