libobs: Remove DrawSrgbDecompressPremultiplied

Technique is no longer referenced, and doesn't seem useful.

libobs/data/default.effect

@@ -69,14 +69,6 @@ float4 PSDrawSrgbDecompress(VertInOut vert_in) : TARGET
 	return rgba;
 }
 
-float4 PSDrawSrgbDecompressPremultiplied(VertInOut vert_in) : TARGET
-{
-	float4 rgba = image.Sample(def_sampler, vert_in.uv);
-	rgba.rgb = max(float3(0.0, 0.0, 0.0), rgba.rgb / rgba.a);
-	rgba.rgb = srgb_nonlinear_to_linear(rgba.rgb);
-	return rgba;
-}
-
 technique Draw
 {
 	pass
@@ -112,12 +104,3 @@ technique DrawSrgbDecompress
 		pixel_shader  = PSDrawSrgbDecompress(vert_in);
 	}
 }
-
-technique DrawSrgbDecompressPremultiplied
-{
-	pass
-	{
-		vertex_shader = VSDefault(vert_in);
-		pixel_shader  = PSDrawSrgbDecompressPremultiplied(vert_in);
-	}
-}

libobs/data/default_rect.effect

@@ -47,14 +47,6 @@ float4 PSDrawSrgbDecompress(VertInOut vert_in) : TARGET
 	return rgba;
 }
 
-float4 PSDrawSrgbDecompressPremultiplied(VertInOut vert_in) : TARGET
-{
-	float4 rgba = image.Sample(def_sampler, vert_in.uv);
-	rgba.rgb = max(float3(0.0, 0.0, 0.0), rgba.rgb / rgba.a);
-	rgba.rgb = srgb_nonlinear_to_linear(rgba.rgb);
-	return rgba;
-}
-
 technique Draw
 {
 	pass
@@ -81,12 +73,3 @@ technique DrawSrgbDecompress
 		pixel_shader  = PSDrawSrgbDecompress(vert_in);
 	}
 }
-
-technique DrawSrgbDecompressPremultiplied
-{
-	pass
-	{
-		vertex_shader = VSDefault(vert_in);
-		pixel_shader  = PSDrawSrgbDecompressPremultiplied(vert_in);
-	}
-}