SPIRV-Tools and tests: Update to location-validation in SPIRV-Tools.

This introduces five new "Validation failures":
- baseResults/hlsl.semantic.vert: issue with gl_ClipDistance/CullDistance
- baseResults/spv.430.vert: issue gl_ClipDistance
- baseResults/spv.450.tesc: still unknown
- baseResults/spv.dataOut.frag: gl_FragData should not be supported, problem with front end
- baseResults/spv.meshShaderPerViewUserDefined.mesh: seems okay, maybe a problem with SPIRV-Tools

Test/baseResults/hlsl.semantic.vert.out

@@ -209,6 +209,7 @@ Shader version: 500
 0:?     '@entryPointOutput.clip1' ( out 2-element array of float ClipDistance)
 0:?     '@entryPointOutput.cull1' ( out 2-element array of float CullDistance)
 
+Validation failed
 // Module Version 10000
 // Generated by (magic number): 8000a
 // Id's are bound by 70

Test/baseResults/spv.430.vert.out

@@ -1,4 +1,5 @@
 spv.430.vert
+Validation failed
 // Module Version 10000
 // Generated by (magic number): 8000a
 // Id's are bound by 66

Test/baseResults/spv.450.tesc.out

@@ -1,4 +1,5 @@
 spv.450.tesc
+Validation failed
 // Module Version 10000
 // Generated by (magic number): 8000a
 // Id's are bound by 45

Test/baseResults/spv.dataOut.frag.out

@@ -1,4 +1,5 @@
 spv.dataOut.frag
+Validation failed
 // Module Version 10000
 // Generated by (magic number): 8000a
 // Id's are bound by 20

Test/baseResults/spv.meshShaderPerViewUserDefined.mesh.out

@@ -1,4 +1,5 @@
 spv.meshShaderPerViewUserDefined.mesh
+Validation failed
 // Module Version 10000
 // Generated by (magic number): 8000a
 // Id's are bound by 108

known_good.json

@@ -5,7 +5,7 @@
       "site" : "github",
       "subrepo" : "KhronosGroup/SPIRV-Tools",
       "subdir" : "External/spirv-tools",
-      "commit" : "e128ab0d624ce7beb08eb9656bb260c597a46d0a"
+      "commit" : "a1fb255a2a6856bba1e5a8486469ac93fca518c2"
     },
     {
       "name" : "spirv-tools/external/spirv-headers",