abuild-rootbld: copy REPODEST value from host to chroot
Otherwise, if a different REPODEST is being used (e.g. due to
buildrepo -d <repo-dest>
) then the abuild invocation in the
created chroot will not write packages to the correct REPODEST.
Therefore, buildrepo -R -d
does presently not work correctly.
This commit fixes this by also copying the REPODEST value from
the environment.
This fixes a regression introduced in 1582617e.