Port a1bd7227
https://crrev.com/c/2129631

Original Commit Message:

  This is the same cleanup as in the previous CL, but for {EmitBinOpImm}.
  This requires a minor change in the name of the emit functions with
  immediate, to make them distinguishable from the emit functions with two
  registers. We just append an "i" to the functions with immediate.

Change-Id: I5089097cb74e204002f0dfcfb6ed10d3ade4da0d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2132346Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Zhao Jiazhong <zhaojiazhong-hf@loongson.cn>
Cr-Commit-Position: refs/heads/master@{#66959}