Much of the gcc_linux_*.c code is identical and duplicated across
architectures. Consolidate code for 386, arm, loong64, mips* and
riscv64, where the only difference is the build tags (386 also
has some non-functional ordering differences).
Change-Id: I14ee9a4cc6b72e165239d196b68b6343efaddf0a
Reviewed-on: https://go-review.googlesource.com/c/go/+/518620
Run-TryBot: Joel Sing <joel@sing.id.au> Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>