This changes DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE() to propagate positive
return values as they were, i.e. stops mapping them all to EXIT_FAILURE. This
was suggested in review, but I thought that we only ever return EXIT_FAILURE,
so we don't need to propagate multiple return values.
I was wrong. Turns out that we already *do* have multiple positive return
values, when we call external binaries and propagate the result. systemd-inhibit
is one example, and b453c447e0 actually broke
this propagation. This commit fixes it.
In systemd-fsck we have the opposite case: we have only one failure value, and the
code needs to be adjusted, so that it keeps returning EXIT_FAILURE.
All other users of DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE() return <= 1, and
are unaffected by this change.
cac0b95790