Change to module directory when loading swiftshader ICD. 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>