PPC only supports the instruction selection for v16i8, v8i16, v4i32, v2i64, v4f32 and v2f64 for ISD::SETCC,
don't support the v1i128, so below IR will crash:
t35: v1i128 = setcc t47, t74, setult:ch
This patch is to set v1i128 to expand for SETCC to avoid crash. And the expanding can get the expected result.