tests: Move HLSL tests to a subdirectory.

Approved-by: Giovanni Mascellani (@giomasce)
Approved-by: Francisco Casas (@fcasas)
Approved-by: Henri Verbeet (@hverbeet)
Approved-by: Alexandre Julliard (@julliard)
Merge-Request: https://gitlab.winehq.org/wine/vkd3d/-/merge_requests/248

tests/hlsl/length.shader_test

@@ -0,0 +1,80 @@
+[pixel shader]
+uniform float4 x;
+
+float4 main() : SV_TARGET
+{
+    return length(x);
+}
+
+[test]
+uniform 0 float4 2.0 3.0 4.0 5.0
+draw quad
+probe all rgba (7.34846926, 7.34846926, 7.34846926, 7.34846926) 1
+
+[pixel shader]
+uniform float3 x;
+
+float4 main() : SV_TARGET
+{
+    return length(x);
+}
+
+[test]
+uniform 0 float4 2.0 3.0 4.0 0.0
+draw quad
+probe all rgba (5.38516474, 5.38516474, 5.38516474, 5.38516474) 1
+
+[pixel shader]
+uniform float2 x;
+
+float4 main() : SV_TARGET
+{
+    return length(x);
+}
+
+[test]
+uniform 0 float4 2.0 3.0 0.0 0.0
+draw quad
+probe all rgba (3.60555124, 3.60555124, 3.60555124, 3.60555124) 1
+
+[pixel shader]
+uniform float1 x;
+
+float4 main() : SV_TARGET
+{
+    return length(x);
+}
+
+[test]
+uniform 0 float4 2.0 0.0 0.0 0.0
+draw quad
+probe all rgba (2.0, 2.0, 2.0, 2.0)
+
+[pixel shader]
+uniform float x;
+
+float4 main() : SV_TARGET
+{
+    return length(x);
+}
+
+[test]
+uniform 0 float4 2.0 0.0 0.0 0.0
+draw quad
+probe all rgba (2.0, 2.0, 2.0, 2.0)
+
+[pixel shader fail]
+uniform float1x3 x;
+
+float4 main() : SV_TARGET
+{
+    return length(x);
+}
+
+[pixel shader fail]
+uniform float4x1 x;
+
+float4 main() : SV_TARGET
+{
+    return length(x);
+}