Renamed DEPTHPARAMS to PIXELCENTERCORRECTION

This shader constant was previously used for depth remapping in D3D and for pixel center correction. Now it only serves one purpose and the new name makes it clear.

Source/Core/VideoCommon/ConstantManager.h

@@ -42,7 +42,7 @@ struct VertexShaderConstants
 	float4 transformmatrices[64];
 	float4 normalmatrices[32];
 	float4 posttransformmatrices[64];
-	float4 depthparams;
+	float4 pixelcentercorrection;
 	float4 stereoparams;
 };