shiny/driver/x11driver: add support for other architectures on linux

Tested on linux/386.

Change-Id: I9a3a2744a0b057e258189780ca29f4bf2a72deb8
Reviewed-on: https://go-review.googlesource.com/31652
Run-TryBot: Minux Ma <minux@golang.org>
Reviewed-by: Nigel Tao <nigeltao@golang.org>
3 files changed