Require custom permission for non-Microdroid

Running with an os other than "microdroid" should require the
USE_CUSTOM_CONFIG permissions (as do our other @TestApi).

Add check, fix up tests.

Bug: 323513087
Test: atest MicrodroidTestApp MicrodroidHostTestCases
Change-Id: If7bc577b275f2a55c80c302ed00d5947676daa6a
diff --git a/virtualizationmanager/src/aidl.rs b/virtualizationmanager/src/aidl.rs
index a2194cc..da842e7 100644
--- a/virtualizationmanager/src/aidl.rs
+++ b/virtualizationmanager/src/aidl.rs
@@ -603,10 +603,14 @@
             } else {
                 // Additional custom features not included in CustomConfig:
                 // - specifying a config file;
-                // - specifying extra APKs.
+                // - specifying extra APKs;
+                // - specifying an OS other than Microdroid.
                 match &config.payload {
                     Payload::ConfigPath(_) => true,
-                    Payload::PayloadConfig(payload_config) => !payload_config.extraApks.is_empty(),
+                    Payload::PayloadConfig(payload_config) => {
+                        !payload_config.extraApks.is_empty()
+                            || payload_config.osName != MICRODROID_OS_NAME
+                    }
                 }
             }
         }