make bootstrap-fixup idempotent

target-bin/bootstrap-fixup.in

@@ -12,11 +12,11 @@ echo '127.0.1.1 gitian' >> /etc/hosts
 # If LXC
 if grep /lxc/gitian /proc/1/cgroup > /dev/null; then
   adduser --disabled-password --gecos ubuntu --quiet ubuntu || true
-  apt-get remove -y rsyslog
+  apt-get remove -y rsyslog || true
   dpkg-divert --local --rename --add /sbin/initctl
-  ln -s /bin/true /sbin/initctl
+  ln -sf /bin/true /sbin/initctl
   dpkg-divert --local --rename --add /usr/bin/ischroot
-  ln -s /bin/true /usr/bin/ischroot
+  ln -sf /bin/true /usr/bin/ischroot
   # Prevent interaction with init during upgrades
   dpkg-divert --local --rename --add /usr/sbin/policy-rc.d
   echo 'exit 101' > /usr/sbin/policy-rc.d