ANDROID: KVM: arm64: pKVM module loading before deprivilege

kvm-arm.protected_modules="" takes a list of modules that pKVM will load
before de-privileging the host. This is necessary as no loading will be
allowed later.

We can't rely on request_module() that might be disabled by umh's
configuration. Instead, create our own version, locked by the pKVM/KVM
static keys and marked as __init to be cleared once the kernel init is
done. Belt and braces.

Keep the previous kvm-arm.protected_modules for compatibility.

Bug: 254835242
Change-Id: Ia6881b4c7a60cf81d19ead12c5d4638a27eff3eb
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>