Feature request: add support for building on IBM AIX

[aklyachkin]

Google Go supports IBM AIX since 1.14 at least with GOOS=aix GOARCH=ppc64.

Building for AIX fails with the following errors:

GOOS=aix GOARCH=ppc64 go build
# github.com/AlecAivazis/survey/v2/terminal
terminal/runereader_posix.go:47:35: undefined: syscall.SYS_IOCTL
terminal/runereader_posix.go:47:81: undefined: ioctlReadTermios
terminal/runereader_posix.go:54:35: undefined: syscall.SYS_IOCTL
terminal/runereader_posix.go:54:81: undefined: ioctlWriteTermios
terminal/runereader_posix.go:62:35: undefined: syscall.SYS_IOCTL
terminal/runereader_posix.go:62:81: undefined: ioctlWriteTermios

The pull request will follow.

[mislav]

Thanks for the request!

Potentially solved by either #372 or #377

[cstes]

I just logged a similar issue for OpenIndiana