Revert "libsnapshot: Don't package snapuserd.rc in /vendor/etc."

This reverts commit 68ba6695bd334b0d582d9b880781d502c4552246.

Bug: 174587489
Test: build and manual inspect

Reason for revert: revert workaround. Fix is in I71227d807244b.

Change-Id: I71b1c0f933eeba9dd8d8fbef3a682657f005cc3b
diff --git a/fs_mgr/libsnapshot/Android.bp b/fs_mgr/libsnapshot/Android.bp
index f441e02..34049d4 100644
--- a/fs_mgr/libsnapshot/Android.bp
+++ b/fs_mgr/libsnapshot/Android.bp
@@ -439,15 +439,7 @@
     static_executable: true,
     system_shared_libs: [],
     ramdisk_available: true,
-}
-
-cc_binary {
-    name: "snapuserd.vendor_ramdisk",
-    stem: "snapuserd",
-    defaults: ["snapuserd_defaults"],
-    static_executable: true,
-    system_shared_libs: [],
-    vendor_ramdisk: true,
+    vendor_ramdisk_available: true,
 }
 
 cc_test {