hw/arm/virt: dt: add kaslr-seed property

hw/arm/virt: dt: add kaslr-seed property

Generate random seeds to be used by the non-secure and/or secure OSes
for ASLR. The seeds are 64-bit random values exported via the DT
properties /chosen/kaslr-seed [1] and /secure-chosen/kaslr-seed, the
latter being used by OP-TEE [2].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e5bc0c37c97e1
[2] https://github.com/OP-TEE/optee_os/commit/ef262691fe0e

Signed-off-by: Jerome Forissier <jerome@forissier.org>
Message-id: 20200420121807.8204-3-jerome@forissier.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>