chore, provide AX_YUCK_SCMVER to populate initial version files

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'bld/dist'

* bld/dist:
  chore, provide AX_YUCK_SCMVER to populate initial version files
chore, ditch GIT_VERSION_MAGIC in favour of AX_YUCK_SCMVER

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'bld/dist'

* bld/dist:
  chore, ditch GIT_VERSION_MAGIC in favour of AX_YUCK_SCMVER