ArmVirtPkg PlatformCI: Support virtio-rng-pci

This patch adds "virtio-rng-pci" to the PlatformBuildLib.py
This adds Rng services to the guest VM

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Leif Lindholm <quic_llindhol@quicinc.com>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>

Signed-off-by: Doug Flick [MSFT] <doug.edk2@gmail.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>

ArmVirtPkg/PlatformCI/PlatformBuildLib.py

@@ -240,6 +240,8 @@ class PlatformBuilder(UefiBuilder, BuildSettingsManager):
         args += " -serial stdio"
         # Mount disk with startup.nsh
         args += f" -drive file=fat:rw:{VirtualDrive},format=raw,media=disk"
+        # Provides Rng services to the Guest VM
+        args += " -device virtio-rng-pci"
 
         # Conditional Args
         if (self.env.GetValue("QEMU_HEADLESS").upper() == "TRUE"):