Remove dead code from scalar_binop

scalar_binop has code for "&&" and "||", but I think this code can't
currently be run -- and, furthermore, it doesn't make sense to have
this code here, as the point of these operators is to short-circuit
evaluation.

This patch removes the dead code.

Regression tested on x86-64 Fedora 36.

Approved-by: Kevin Buettner <kevinb@redhat.com>