runtime: fix breakpoint in ppc64x
Currently runtime.Breakpoint generates a SIGSEGV in ppc64.
The solution is an unconditional trap similar to what clang and gcc do. It is documented in the section C.6 of the ABI Book 3.
Fixes #52101
Change-Id: I071d2f2679b695ef268445b04c9222bd74e1f9af
GitHub-Last-Rev:
fff4e5e8ffe23bf0cef135b22abd2cc0a3838613
GitHub-Pull-Request: golang/go#52102
Reviewed-on: https://go-review.googlesource.com/c/go/+/397554
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Paul Murphy <murp@ibm.com>
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>