update to use HID spec protocol value for get/set_protocol()

src/class/hid/hid.h

@@ -142,11 +142,11 @@ typedef enum
 } hid_local_enum_t;
 
 // HID protocol value used by GetProtocol / SetProtocol
-enum
+typedef enum
 {
   HID_PROTOCOL_BOOT = 0,
   HID_PROTOCOL_REPORT = 1
-};
+} hid_protocol_mode_enum_t;
 
 /** @} */