Move systemd handling to a new late_init() function in posix.c.
This prepares a future removal of the NO_SOCKETS macro.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>