GN: Build libVulkan to root_out_dir.

This allows the TSAN/ASAN builds to properly locate the library.
Makes the fuchsia workaround apply everywhere.

Bug: chromium:1000668
Bug: angleproject:3876
Change-Id: Ide2e8527c89c614a648204e953def1f24b702a62
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/36468
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Tested-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>

src/Vulkan/BUILD.gn

diff --git a/src/Vulkan/BUILD.gn b/src/Vulkan/BUILD.gn
index c2e63d6..8c6141b 100644
--- a/src/Vulkan/BUILD.gn
+++ b/src/Vulkan/BUILD.gn
@@ -129,10 +129,6 @@
   } else {
     output_name = "libvk_swiftshader"
   }
-  if (!is_fuchsia) {
-    # NOTE: Work-around for http://crbug.com/1000668
-    output_dir = "$root_out_dir/swiftshader"
-  }
 
   if (is_mac) {
     ldflags = [