Update loader to version that will make sure the
VK_ICD_FILENAMES env variable is always picked up on Windows.

Bug: angleproject:2464
Change-Id: I6c161c00e0af708f288f59fc62b9cb9d6f131626
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1876451Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Tobin Ehlis <tobine@google.com>