[linux-aws][BDE] RANDOM_TRUST_BOOTLOADER support on AWS Graviton

[Kamal Mostafa]

BugLink: https://bugs.launchpad.net/bugs/1859192

As requested by AWS, the following pull reqs cherry-pick two mainline commits
to linux-aws [BDE] kernels.


AWS Graviton (arm64) instance types gain a boot speed benefit by
application of the following two commits from mainline v5.4:

428826f5358c fdt: add support for rng-seed
18b915ac6b0a efi/random: Treat EFI_RNG_PROTOCOL output as bootloader randomness

and enable CONFIG_RANDOM_TRUST_BOOTLOADER=y (for arm64 only)

 -Kamal