Enable GPU in crosvm

When the GPU feature is turned on in crosvm, these modules are added as
dependencies. Since crosvm is included in the virt APEX, add the APEX to
the apex_available properties of the modules to make them available in
the APEX.

Bug: 325929966
Test: m
Change-Id: If1435570fd5697af3b9989f0477014452456acbc
diff --git a/lib/Android.bp b/lib/Android.bp
index 03bd6a2..ecdeda0 100644
--- a/lib/Android.bp
+++ b/lib/Android.bp
@@ -24,6 +24,7 @@
         "com.android.adbd",
         "com.android.art", // from libartbase
         "com.android.art.debug",
+        "com.android.virt",
     ],
     recovery_available: true,
     vendor_available: true,