cmd/compile: encoding/binary.PutUint16 sometimes doesn't write [1.20 backport]

[gopherbot]

@randall77 requested issue #59367 to be considered for backport to the next 1.20 minor release.

@gopherbot please open backport issues for 1.20 and 1.19.

[gopherbot]

Change https://go.dev/cl/483176 mentions this issue: [release-branch.go1.20] cmd/compile: use correct type for byteswaps on multi-byte stores

[gopherbot]

Closed by merging 0684cec to release-branch.go1.20.