erts: Clarify *_to_existing_atom documentation
erts: Clarify *_to_existing_atom documentation

getong/otp,rlipscombe/otp,jj1bdx/otp,rlipscombe/otp,dgud/otp,getong/otp,jj1bdx/otp,potatosalad/otp,dumbbell/otp,getong/otp,jj1bdx/otp,isvilen/otp,uabboli/otp,mikpe/otp,uabboli/otp,dgud/otp,emacsmirror/erlang,jj1bdx/otp,bjorng/otp,uabboli/otp,isvilen/otp,rlipscombe/otp,jj1bdx/otp,dgud/otp,uabboli/otp,getong/otp,isvilen/otp,erlang/otp,g-andrade/otp,emacsmirror/erlang,ferd/otp,ferd/otp,vinoski/otp,emacsmirror/erlang,uabboli/otp,ferd/otp,getong/otp,erlang/otp,g-andrade/otp,bjorng/otp,bjorng/otp,potatosalad/otp,dumbbell/otp,getong/otp,dumbbell/otp,uabboli/otp,vinoski/otp,vinoski/otp,dumbbell/otp,bjorng/otp,dgud/otp,emacsmirror/erlang,potatosalad/otp,ferd/otp,getong/otp,mikpe/otp,potatosalad/otp,isvilen/otp,erlang/otp,mikpe/otp,erlang/otp,isvilen/otp,rlipscombe/otp,vinoski/otp,isvilen/otp,getong/otp,dumbbell/otp,g-andrade/otp,ferd/otp,mikpe/otp,bjorng/otp,emacsmirror/erlang,erlang/otp,erlang/otp,erlang/otp,potatosalad/otp,mikpe/otp,potatosalad/otp,g-andrade/otp,erlang/otp,rlipscombe/otp,dumbbell/otp,dgud/otp,dumbbell/otp,emacsmirror/erlang,isvilen/otp,vinoski/otp,rlipscombe/otp,dgud/otp,vinoski/otp,jj1bdx/otp,potatosalad/otp,emacsmirror/erlang,g-andrade/otp,g-andrade/otp,g-andrade/otp,vinoski/otp,rlipscombe/otp,dgud/otp,ferd/otp,g-andrade/otp,erlang/otp,bjorng/otp,vinoski/otp,uabboli/otp,mikpe/otp,uabboli/otp,vinoski/otp,ferd/otp,dgud/otp,vinoski/otp,dumbbell/otp,g-andrade/otp,getong/otp,ferd/otp,potatosalad/otp,dumbbell/otp,mikpe/otp,getong/otp,rlipscombe/otp,isvilen/otp,rlipscombe/otp,dgud/otp,bjorng/otp,mikpe/otp,erlang/otp,jj1bdx/otp,jj1bdx/otp,emacsmirror/erlang,bjorng/otp,emacsmirror/erlang,mikpe/otp,jj1bdx/otp,jj1bdx/otp,bjorng/otp,ferd/otp,dgud/otp,isvilen/otp,potatosalad/otp,g-andrade/otp,isvilen/otp,rlipscombe/otp,mikpe/otp,uabboli/otp,dumbbell/otp,bjorng/otp,potatosalad/otp,emacsmirror/erlang