hafnium: revert to use semicolon separator in the RUN command

revert https://review.trustedfirmware.org/c/ci/dockerfiles/+/6672
It was working as expected, as long as we keep "set -e" in the RUN
command.

Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
Change-Id: Ifb6e0f6c3cbb781013eeaafd7d037dc528749378
1 file changed