fix div_s ops, they need to trap on overflow
fix div_s ops, they need to trap on overflow

(i32.div_s (i32.const 0x80000000) (i32.const -1)) is supposed to trap.
The similar i64.div_s operation should also trap.

WebAssembly/wabt,citisolo/wabt,WebAssembly/wabt,citisolo/wabt,WebAssembly/sexpr-wasm-prototype,WebAssembly/sexpr-wasm-prototype,citisolo/wabt,citisolo/wabt,citisolo/wabt,WebAssembly/sexpr-wasm-prototype,WebAssembly/wabt,WebAssembly/sexpr-wasm-prototype,WebAssembly/sexpr-wasm-prototype,citisolo/wabt,WebAssembly/wabt,WebAssembly/wabt,WebAssembly/sexpr-wasm-prototype