Add assemble_cvd to com.android.virt

assemble_cvd directly or indirectly depends on these modules. To add
assemble_cvd to the com.anroid.virt APEX, these modules are marked as
being available to the APEX.

Bug: 174639526
Test: m com.android.virt
Change-Id: Icb235148e13b29058d0d9d34fae37ea8340ed44c
diff --git a/Android.bp b/Android.bp
index e61e1a0..ab6acf4 100644
--- a/Android.bp
+++ b/Android.bp
@@ -37,6 +37,10 @@
     host_supported: true,
     vendor_available: true,
     sdk_version: "24",
+    apex_available: [
+        "//apex_available:platform",
+        "com.android.virt",
+    ],
 }
 
 // This module makes Vulkan headers available to vendor code that is