cmd/compile: use correct type in amd64 late-lower rules
The wrong type causes the wrong width spill, which corrupts
the value. I tried to write a test for this and did not
succeed, but was able (using gossahash and ssa.html) to
isolate to exact change and spill.
Fixes #59432.
Change-Id: I85ad82c9f8fed7674c69d6a2b0a62e111f690454
Reviewed-on: https://go-review.googlesource.com/c/go/+/482536 Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>