support/testing: drop haveged for python tests

support/testing: drop haveged for python tests

The new builtin armv5 kernel 4.19 uses VirtIORNG to provide entropy, so we
no longer need haveged.

Fixes:
https://gitlab.com/buildroot.org/buildroot/-/jobs/264508536
https://gitlab.com/buildroot.org/buildroot/-/jobs/264508537
https://gitlab.com/buildroot.org/buildroot/-/jobs/264508542
https://gitlab.com/buildroot.org/buildroot/-/jobs/264508543

Signed-off-by: Ricardo Martincoski <ricardo.martincoski@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
[Peter: reword]
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>