It appears that when we import github.com/coreos/go-systemd/activation,
it brings in the whole crypto/tls package (which is not used by runc
directly or indirectly), making the runc binary size larger and
potentially creating issues with FIPS compliance.
Let's copy the code of function we use from go-systemd/activation
to avoid that.
The space savings are:
$ size runc.before runc.after
text data bss dec hex filename
7101084 5049593 271560 12422237 bd8c5d runc.before
6508796 4623281 229128 11361205 ad5bb5 runc.after
Reported-by: Dimitri John Ledkov <dimitri.ledkov@surgut.co.uk>
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>