Implement these 4 instructions for ia32 Liftoff:
- i64x2.widen_low_i32x4_s
- i64x2.widen_high_i32x4_s
- i64x2.widen_low_i32x4_u
- i64x2.widen_high_i32x4_u

We move the codegen for the *high* instructions into macro-assembler to
allow sharing of the optimized code sequence between TurboFan and
Liftoff.

Bug: v8:10972
Change-Id: Ib5c6cbf6d4a39ef298298b75516f5221cb8ec249
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2621863
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Bill Budge <bbudge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72059}