On {mips,mips64,ppc,s390}, target addresses are specially coded into
the instruction stream, i.e. split between a series of instructions.
This adds support for that case, similar to what happens with runtime
external references.

Bug: v8:6666,v8:7571
Change-Id: Ie6f62bc0ca3183f005d8380f6f8b908fa12ea62b
Reviewed-on: https://chromium-review.googlesource.com/970824
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52091}