Revert "perf test 6: Fix missing kvm module load for s390"

This reverts commit 9a501cdb.

Which was upstream commit 53fe307d

.

Ben Hutchings reports that this commit depends on new code added in
v4.18, and so is irrelevant on older kernels, and breaks the build.

Signed-off-by: Sasha Levin <sashal@kernel.org>