tests: Add a test for shader point size output.

Approved-by: Henri Verbeet (@hverbeet)
Merge-Request: https://gitlab.winehq.org/wine/vkd3d/-/merge_requests/1146

tests/hlsl/shader-point-size.shader_test

@@ -0,0 +1,34 @@
+[require]
+shader model < 4.0
+
+[input layout]
+0 r32g32-float position
+0 r32-float psize
+
+[vb 0]
+-0.5 0      20
+ 0.5 0      40
+
+[vertex shader]
+void main(inout float4 pos : position, inout float size : psize)
+{
+}
+
+[pixel shader]
+float4 main() : color
+{
+    return float4(0, 1, 0, 1);
+}
+
+[test]
+draw point list 2
+
+probe (149, 240) rgba (0, 0, 0, 0)
+todo probe (151, 240) rgba (0, 1, 0, 1)
+todo probe (169, 240) rgba (0, 1, 0, 1)
+probe (171, 240) rgba (0, 0, 0, 0)
+
+probe (459, 240) rgba (0, 0, 0, 0)
+todo probe (461, 240) rgba (0, 1, 0, 1)
+todo probe (499, 240) rgba (0, 1, 0, 1)
+probe (501, 240) rgba (0, 0, 0, 0)