Fix reinterpret shader for D3D11

Common/GPU/Shader.cpp

@@ -74,6 +74,7 @@ void ShaderLanguageDesc::Init(ShaderLanguage lang) {
 		forceMatrix4x4 = false;
 		coefsFromBuffers = true;
 		vsOutPrefix = "Out.";
+		viewportYSign = "-";
 		break;
 	}
 }

Common/GPU/Shader.h

@@ -45,6 +45,7 @@ struct ShaderLanguageDesc {
 	const char *lastFragData = nullptr;
 	const char *framebufferFetchExtension = nullptr;
 	const char *vsOutPrefix = "";
+	const char *viewportYSign = "";
 	bool glslES30 = false;
 	bool bitwiseOps = false;
 	bool forceMatrix4x4 = false;

GPU/Common/ReinterpretFramebuffer.cpp

@@ -75,6 +75,7 @@ bool GenerateReinterpretVertexShader(char *buffer, const ShaderLanguageDesc &lan
 	writer.C("  float x = -1.0 + float((gl_VertexIndex & 1) << 2);\n");
 	writer.C("  float y = -1.0 + float((gl_VertexIndex & 2) << 1);\n");
 	writer.C("  v_texcoord = (vec2(x, y) + vec2(1.0, 1.0)) * 0.5;\n");
+	writer.F("  y *= %s1.0;\n", lang.viewportYSign);
 	writer.C("  gl_Position = vec4(x, y, 0.0, 1.0);\n");
 
 	writer.EndVSMain(varyings);