HLSL Color Transforms and 3D LUT (#4043)

* Remove broken scanline uniform from post_pass

* Add 3D LUT to HLSL

* Allow individual LUTs for screen and UI

* WIP: Port 3D LUT to BGFX

* Finish porting LUT to BGFX

* Add individual phosphor color conversion for HLSL
	new file:   hlsl/chroma.fx
		Shader for converting xyY3 to sRGB
	modified:   hlsl/phosphor.fx
		Minor changes to emphasize idea that phosphors are color
agnostic
	modified:   hlsl/post.fx
		Conversion from signal RGB to xyY3
	modified:   src/osd/modules/render/d3d/d3dhlsl.cpp
	modified:   src/osd/modules/render/d3d/d3dhlsl.h
	modified:   src/osd/windows/winmain.cpp
	modified:   src/osd/windows/winmain.h

* Add phosphor examples and update presets

* Port phosphor color shaders to BGFX

* Fix missing newlines at EOF

Author: anikom15

bgfx/chains/hlsl.json

@@ -0,0 +1,36 @@
+{
+	"name": "3D LUT",
+	"author": "W. M. Martinez",
+	"targets": [
+		{
+			"name": "temp",
+			"mode": "guest"
+		}
+	],
+	"passes": [
+		{
+			"effect": "misc/blit",
+			"name": "Copy To Filtered Texture",
+			"input": [
+				{ "sampler": "s_tex", "texture": "screen" }
+			],
+			"output": "temp"
+		}, {
+			"effect": "misc/lut",
+			"name": "Apply LUT",
+			"input": [
+				{
+					"sampler": "s_tex",
+					"target": "temp"
+				}, {
+					"sampler": "s_3dlut",
+					"option": "bgfx_lut",
+					"bilinear": false,
+					"clamp": true,
+					"selection": "LUT Texture"
+				}
+			],
+			"output": "output"
+		}
+	]
+}