Comment # 1 on bug 1034938 from Franck Bui

Due to bsc#1024740, we stopped generating /etc/machine-id during systemd
package installation.

This makes the specifier '%m' unavailable in the tmpfiles.d configuration files
at this time hence the warnings you're seeing (systemd package uses
%tmpfiles_create rpm macro in its %post).

Those warnings should be harmless although it would be better if we silent
them.

Ok let make it simple for now and use "%tmpfiles_create 2>/dev/null", after all
that's how the macro was implemented originally.