OvmfPkg/VirtioNetDxe: add helper VirtioNetUninitRing()

Consolidate the virtio VRING resource cleanup into VirtioNetUninitRing().

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>

OvmfPkg/VirtioNetDxe/SnpSharedHelpers.c

@@ -51,3 +51,19 @@ VirtioNetShutdownTx (
 {
   FreePool (Dev->TxFreeStack);
 }
+
+/**
+  Release TX and RX VRING resources.
+
+  @param[in,out] Dev   The VNET_DEV driver instance which was using the ring.
+  @param[in,out] Ring  The virtio ring to clean up.
+*/
+VOID
+EFIAPI
+VirtioNetUninitRing (
+  IN OUT VNET_DEV *Dev,
+  IN OUT VRING    *Ring
+  )
+{
+  VirtioRingUninit (Dev->VirtIo, Ring);
+}