When loading vulkan, we can be running from any directory. We need
to change to the module directory to ensure the swiftshader ICD is
loaded properly. For example, in some Chrome releases, libGLESv2.dll
and libvk_swiftshader.dll are in a subdirectory relative to chrome.exe

Bug: chromium:1198567
Change-Id: I9e68927e512b239728fb2903d1a04702508a4948
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2873452
Commit-Queue: Jonah Ryan-Davis <jonahr@google.com>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>