commit ab88632835 changed the path for
the pause.pid file but didn't update the same path in the C code.
This prevented Podman to take the fast path when the userns is already
created and to join it without re-execing itself.
Fix the path in the C code as well so we can join the rootless
user+mount namespace without having to re-exec Podman.
[NO TESTS NEEDED]
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
(cherry picked from commit 11badab046)