unetd: fix PKG_MIRROR_HASH

unetd: fix PKG_MIRROR_HASH

Our CI on GitHub as well as my local machine generates a different
PKG_MIRROR_HASH from what Felix uploaded the other day.

After receiving Felix file, both have indeed different hashes, however
when unpackaged via `xz -d` both have the same tarball content.

Below the checksums to compare:

a62bef497078c7b825f11fc8358c1a43f5db3e6d4b97812044f7653d60747d5b  dl/unetd-2024.03.31~80645766.tar.xz
fbdac59581742bf208c18995b1d69d9848c93bfce487e57ba780d959e0d62fc4  dl/unetd-2024.03.31~80645766_felix.tar.xz

After unpacking:

a7189cae90bc600abf3a3bff3620dc17a9143be8c27d27412de6eb66a1cf1b7d  dl/unetd-2024.03.31~80645766.tar
a7189cae90bc600abf3a3bff3620dc17a9143be8c27d27412de6eb66a1cf1b7d  dl/unetd-2024.03.31~80645766_felix.tar

The tarball with the wrong hash was accidentally generated without the xz
revert to version 5.4.6

Signed-off-by: Paul Spooren <mail@aparcar.org>