minor, allow no left hand side in tzconv.m mex

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'contrib/mex-tzconv' into next

* contrib/mex-tzconv:
  minor, allow no left hand side in tzconv.m mex
minor, avoid c99 (reverse) inlines and provide a public dt_to_unix_epoch() and dt_to_gps_epoch()

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
chore, hygiene, eliminate __to_unix_epoch() copy in ltrcc, use public dt_to_unix_epoch() instead

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
hygiene, rewrite tuidiv()/tuimod() calls in dt_tadd() in terms of divrem() inline

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
chore, lift inlining pressure from divrem() helper

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
chore, lift inlining pressure from __offs() offset finder in tzraw

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'code/hygiene' into next

* code/hygiene:
  chore, lift inlining pressure from __offs() offset finder in tzraw
  chore, lift inlining pressure from divrem() helper
  hygiene, rewrite tuidiv()/tuimod() calls in dt_tadd() in terms of divrem() inline
  chore, hygiene, eliminate __to_unix_epoch() copy in ltrcc, use public dt_to_unix_epoch() instead
  minor, avoid c99 (reverse) inlines and provide a public dt_to_unix_epoch() and dt_to_gps_epoch()