erts: Make bs_get_tail create a heapbin if possible
erts: Make bs_get_tail create a heapbin if possible

When getting the tail of a match context, we create
a heapbin instead of a subbin if the size of the
tail is smaller than the size of a subbin.

This is already done in the JIT.

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