Don't WTF if getSystemService(VIRTUALIZATION_SERVICE) returns null

On devices without AVF support it is expected for the
Context.getSystemService(VIRTUALIZATION_SERVICE) to return null.

Bug: 261012673
Test: atest CtsMicrodroidDisabledTestCases
Change-Id: I4e0f0efe8e8a128dc79f22f39175a2cee7724251

core/java/android/app/SystemServiceRegistry.java

@@ -1617,6 +1617,7 @@ public final class SystemServiceRegistry {
                 case Context.INCREMENTAL_SERVICE:
                 case Context.ETHERNET_SERVICE:
                 case Context.CONTEXTHUB_SERVICE:
+                case Context.VIRTUALIZATION_SERVICE:
                     return null;
             }
             Slog.wtf(TAG, "Manager wrapper not available: " + name);