adderall.dsl: Simplify all and eitherᵍ

Use (yield-from) to simplify (all) and (eitherᵍ) a bit.

Signed-off-by: Gergely Nagy <algernon@balabit.hu>
adderall.dsl: Use defmacro/g! for Zzz

Signed-off-by: Gergely Nagy <algernon@balabit.hu>
adderall.dsl: Factor --prep-fresh-vars-- out of run and fresh

Both fresh and run were using the same code to prepare frest LVars, so
lifted that out into a common function.

Signed-off-by: Gergely Nagy <algernon@balabit.hu>