Make apex availability of libfuse explicit

The availability to com.android.mediaprovider was done implicitly using a baseline map in
build/soong/apex/apex.go. Make this explicit in Android.bp

libfuse also requires //apex_available:platform in its
apex_available. This lib gets installed in vendor, and
//apex_available:platform is required on all non-apex variants including
the vendor variants

Bug: 281077552
Test: m nothing

Change-Id: I4158aa230c434156c27de912c4e992876bd0e2fb
diff --git a/Android.bp b/Android.bp
index 5373206..aabfce5 100644
--- a/Android.bp
+++ b/Android.bp
@@ -97,4 +97,9 @@
         "lib/mount.c",
         "lib/mount_util.c",
     ],
+
+    apex_available: [
+        "//apex_available:platform",
+        "com.android.mediaprovider",
+    ],
 }