There is no way for gzip 1.2.4 and tar 1.12 to disable the inclusion of
timestamps into the tarball/gzip, which creates non-reproducible
tarballs and hence packages.
While it is theoretically possible to set the timestamps to unix time 0
using touch, in reality this is not possible because mes libc does not
support utime() which sets the timestamp of a file from userspace. So we
need to ignore it rather than (re)set it.