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/sample-bias.shader_test

@@ -0,0 +1,43 @@
+[sampler 0]
+filter linear linear linear
+address clamp clamp clamp
+
+[texture 0]
+size (2, 2)
+levels 2
+
+1.0 0.0 1.0 0.0     1.0 0.0 1.0 0.0
+1.0 0.0 1.0 0.0     1.0 0.0 1.0 0.0
+
+0.0 0.0 1.0 0.0
+
+[vertex shader]
+void main(out float2 tex : texcoord, inout float4 pos : sv_position)
+{
+    tex = pos.xy;
+}
+
+[pixel shader]
+sampler s;
+Texture2D t;
+uniform float bias;
+
+float4 main(float2 coord : texcoord) : sv_target
+{
+    /* Choice of initial mipmap level is hardware-dependent, and in practice
+     * varies too much to be reasonably covered by ULPS. Quantize instead. */
+    return floor(t.SampleBias(s, coord, bias) * 10);
+}
+
+[test]
+uniform 0 float4 6.5 0.0 0.0 0.0
+draw quad
+probe all rgba (10.0, 0.0, 10.0, 0.0)
+
+uniform 0 float4 7.5 0.0 0.0 0.0
+draw quad
+probe all rgba (4.0, 0.0, 10.0, 0.0)
+
+uniform 0 float4 8.5 0.0 0.0 0.0
+draw quad
+probe all rgba (0.0, 0.0, 10.0, 0.0)