cmd/compile: Go 1.22.x failed to be bootstrapped from 386 to ppc64le [1.22 backport]

[gopherbot]

@pmur requested issue #66955 to be considered for backport to the next 1.22 minor release.

@gopherbot please consider a backport to go 1.22. This prevents crosscompiling ppc64x code on 32 bit hosts.

[gopherbot]

Change https://go.dev/cl/581455 mentions this issue: [release-branch.go1.22] cmd/internal/obj/ppc64: fix incorrect int to int64 conversion when checking MOVD opcodes

[gopherbot]

Closed by merging 12c1177 to release-branch.go1.22.