hexagon container update

[Brian Cain]

Alex,

We need to update the docker container used for hexagon for new test cases 
proposed in Taylor's recent patch series under review.  Thankfully, CodeLinaro 
has provided a binary of the hexagon cross toolchain so now I think we can 
simplify the hexagon docker file to something like the below.  I hope this also 
means that we can remove the exceptional handling for the hexagon container.

I can propose a patch but I'm not quite certain how to test it.

The "--no-check-certificate" argument to wget is very bad but I'm not quite 
certain how to upgrade/change the container's certificate store to accept the 
apparently-legit-but-perhaps-newer-than-expected certificate presented by 
codelinaro.jfrog.io.

~~~

FROM qemu/debian10

RUN apt update && \
        DEBIAN_FRONTEND=noninteractive apt install -yy eatmydata && \
        DEBIAN_FRONTEND=noninteractive eatmydata \
        apt install -y --no-install-recommends \
        xz-utils \
        wget

ENV CLANG_URL 
https://codelinaro.jfrog.io/artifactory/codelinaro-toolchain-for-hexagon/v2021.09.10/clang+llvm-Sept-2021-cross-hexagon-unknown-linux-musl.tar.xz

RUN cd /tmp && \
    wget --quiet --no-check-certificate ${CLANG_URL}
RUN cd /opt && \
    tar xf /tmp/clang+llvm-Sept-2021-cross-hexagon-unknown-linux-musl.tar.xz