Fix stdin is not a tty

$ docker run 103a74f4671d /bin/bash -lc '/script/arch_version'
    stdin: is not a tty
    Linux_3.16.3-1-ARCH_x86_64
    $ docker run 103a74f4671d /bin/bash -c '/script/arch_version'
    Linux_3.16.3-1-ARCH_x86_64

@nahiluhmot /cc @adamjt @bfulton