Revert "xbps-src: do not propagate -H into XBPS_OPTIONS; the hostdir has a fixed path in the chroot."

This reverts commit f682eb7ec6d4553f89e32d88df53d12b91eb397c.
xbps-src: partial revert of 871d2fa87.

We can't pass XBPS_OPTIONS to xbps-uchroot(8) as is.