util: Specify version of rocm-cmake in gcn3 Dockerfile

util: Specify version of rocm-cmake in gcn3 Dockerfile

This patch updates the gcn3 Dockerfile to use the version of rocm-cmake
that MIOpen specifies in its dev-requirements.txt. This fixes a build
conflict with newer versions of rocm-cmake that require a higher version
of SCons than we have in the Dockerfile.

Change-Id: I70887fd91807b77e5015037830cfe96560ac8a31
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/37155
Maintainer: Gabe Black <gabe.black@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>