test, make a comparison in struct-7 test actually

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Revert "fix, PEBKAC, don't pass uninitialised args to dt_strfdt()"

This reverts commit f8e999dba384b0dd94aa718a1a6ad6f9927c6523.
Revert "minor, extend dt_strfdt() to take a zdiff parameter, ..."

This reverts commit 420d65d36d0eade22a210c3379da37f392ec0046.
Revert "minor, use pointers in dtz_forgetz() and dtz_enrichz() and return the difference applied"

This reverts commit 88092348e8318da238622c1034df2868b55d2d55.
minor, bring back zdiff handling (and %Z)

Squeeze the time zone difference in a struct dt_dt_s' 6bits of
space left by struct dt_d_s.
This means zone differences range from -16 hours to +16 hours
with a resolution of 15 minutes.

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'feat/zdiff-in-dt_s' into next

* feat/zdiff-in-dt_s:
  minor, bring back zdiff handling (and %Z)
  Revert "minor, use pointers in dtz_forgetz() and dtz_enrichz() and return the difference applied"
  Revert "minor, extend dt_strfdt() to take a zdiff parameter, ..."
  Revert "fix, PEBKAC, don't pass uninitialised args to dt_strfdt()"
  test, make a comparison in struct-7 test actually