[meta-xilinx] Failed to init entropy source hwrng

[Arno Steffens]

Build a rootfs with Yocto 2.5 and 3.0 (Zeus). Got both working, but booting in 3.0 is terrible slow.
The reasons seems to be that random numbers are not generated for ssh. I found that there is a new startup script:
/etc/init.d/rng-tools
that needs around 14s. But if I comment it out, it ssh needs even 86s!

Please help, what can I do to get same fast timing as in 2.5? I would rather go lower security than waiting for 14 seconds.
I am running a 4.19 vanilla kernel with some xilinx patches. Do I miss one?

Output in boot-log>:
...
run-parts: /etc/network/if-pre-up.d/nfsroot: exit status 1
Starting random number generator daemon
Initializing available sources

Failed to init entropy source hwrng

Initializing AES buffer

Enabling JITTER rng support

Initializing entropy source jitter

.
random: crng init done
Starting OpenBSD Secure Shell server: sshd