Camera: Add HAL module init method.

For use by Camera HAL libraries to perform one-time initialization
steps after the library is loaded.

Bug: 20016050
Change-Id: Ia01ae0eafcadece9124ac2cfcc3b1c3939352843
diff --git a/modules/usbcamera/CameraHAL.cpp b/modules/usbcamera/CameraHAL.cpp
index 98111ef..652e937 100644
--- a/modules/usbcamera/CameraHAL.cpp
+++ b/modules/usbcamera/CameraHAL.cpp
@@ -147,6 +147,7 @@
     get_vendor_tag_ops    : NULL,
     open_legacy           : NULL,
     set_torch_mode        : NULL,
+    init                  : NULL,
     reserved              : {0},
 };
 } // extern "C"