Revert "Fix VTS Fuzz issue"

This reverts commit 1adfae9364f83e5df8aa695394c3262a867e80f0.

Reason for revert: Causes Sabrina/Boreal bt stacks to timeout on startup
Bug: 247053367

Change-Id: Ibef97f054510c826920bb30725fed168c755cc14
diff --git a/bluetooth/1.0/default/vendor_interface.h b/bluetooth/1.0/default/vendor_interface.h
index 2df3946..040f31a 100644
--- a/bluetooth/1.0/default/vendor_interface.h
+++ b/bluetooth/1.0/default/vendor_interface.h
@@ -22,8 +22,6 @@
 #include "bt_vendor_lib.h"
 #include "hci_protocol.h"
 
-extern std::mutex initcb_mutex_;
-
 namespace android {
 namespace hardware {
 namespace bluetooth {
@@ -47,9 +45,10 @@
   size_t Send(uint8_t type, const uint8_t* data, size_t length);
 
   void OnFirmwareConfigured(uint8_t result);
-  virtual ~VendorInterface() = default;
 
  private:
+  virtual ~VendorInterface() = default;
+
   bool Open(InitializeCompleteCallback initialize_complete_cb,
             PacketReadCallback event_cb, PacketReadCallback acl_cb,
             PacketReadCallback sco_cb, PacketReadCallback iso_cb);