Add guest mode functionality (1/3)

Add a flag to enable() to start Bluetooth in restricted
mode. In restricted mode, all devices that are paired during
restricted mode are deleted upon leaving restricted mode.
Right now restricted mode is only entered while a guest
user is active

Bug: 27410683
Change-Id: I994a2933fd60301927ff2df65da634f81d4c9428
(cherry picked from commit 4048610354bc6fff0eea733d46df502a29487b9f)
diff --git a/include/hardware/bluetooth.h b/include/hardware/bluetooth.h
index 0f1a35b..68cbd1e 100644
--- a/include/hardware/bluetooth.h
+++ b/include/hardware/bluetooth.h
@@ -438,7 +438,7 @@
     int (*init)(bt_callbacks_t* callbacks );
 
     /** Enable Bluetooth. */
-    int (*enable)(void);
+    int (*enable)(bool guest_mode);
 
     /** Disable Bluetooth. */
     int (*disable)(void);