[csrng/dv] Avoid push data assertion for fifo write error injection
[csrng/dv] Avoid push data assertion for fifo write error injection

Signed-off-by: Marno van der Maas <140765e35f75d33bd28eb112371bcce78847cb8a@lowrisc.org>

lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan