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/arithmetic-float.shader_test

@@ -0,0 +1,68 @@
+[pixel shader]
+float4 main() : SV_TARGET
+{
+    float x = 5.0;
+    float y = 15.0;
+
+    return float4(x + y, x - y, x * y, x / y);
+}
+
+[test]
+draw quad
+probe all rgba (20.0, -10.0, 75.0, 0.33333333)
+
+[pixel shader]
+float4 main() : SV_TARGET
+{
+    float x = 5.0;
+    float y = 15.0;
+
+    return float4(x % y, +x, -x, y / x);
+}
+
+[test]
+draw quad
+probe all rgba (5.0, 5.0, -5.0, 3.0)
+
+[pixel shader]
+float4 main() : SV_TARGET
+{
+    float x = 42;
+    float y = 5;
+
+    return float4(x % y, -x % y, x % -y, -x % -y);
+}
+
+[test]
+draw quad
+probe all rgba (2.0, -2.0, 2.0, -2.0) 16
+
+[pixel shader]
+float4 main() : SV_TARGET
+{
+    float x = 45;
+    float y = 5;
+
+    return float4(x % y, -x % y, x % -y, -x % -y);
+}
+
+[test]
+draw quad
+probe all rgba (0.0, 0.0, 0.0, 0.0)
+
+[require]
+% Infinities are not allowed in SM1
+shader model >= 4.0
+
+[pixel shader]
+float4 main() : SV_TARGET
+{
+    float x = 1;
+    float y = 0;
+
+    return x / y;
+}
+
+[test]
+draw quad
+probe all rgba (1e99, 1e99, 1e99, 1e99)