Vulkan: Very minor "rx::vk::BindingPointer" move-ctor update. Initialize "mRefCounted" in member initializer list to avoid unnecessary initialization with "nullptr" provided by the default member initializer. Optimizer will eliminate extra store in release builds but not in debug. This change is more for code cleanness than for performance. Bug: None Change-Id: I1127a543468bb4138ae12d8941af27591ec4a2e8 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4251638 Commit-Queue: Igor Nazarov <i.nazarov@samsung.com> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>