I've theorised that a parallel build-tcg is somehow getting confused
when two fedora-30 based cross compilers attempt to build at the same
time. From one data-point so far this may fix the problem although the
plugins job runs quite close to timeout.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200203090932.19147-18-alex.bennee@linaro.org>