Bionic requires random numbers to init the shadow call stack. Those
numbers are obtained via the syscall getrandom (non-blocking) and will
fallback to /dev/urandom if the former fails.
When loading pKVM modules, we are so early in the boot process that the
only source of entropy for the linux RNG are the architecture random
number generators... which might be available on some platforms. Without
any source of entropy, the only way of generating a random number is to
try to generate some, which is what the bionic fallback expects via
urandom.
As a consequence, add the urandom node to the initramfs.
Bug: 274876849
Merged-In: I111e2db53fabd63d070b8e9ab9c52faebf484ab3
Change-Id: I34a0e3f7c72de7344512366d4a96183b445edc2e
e80a6b6dd4