Private->Function variables, fragment output, geometry shader tweaks.

src/xenia/gpu/vulkan/shaders/rect_list.geom

@@ -1,7 +1,7 @@
 // NOTE: This file is compiled and embedded into the exe.
 //       Use `xenia-build genspirv` and check in any changes under bin/.
 
-#version 450
+#version 450 core
 #extension all : warn
 
 in gl_PerVertex {
@@ -19,8 +19,8 @@ out gl_PerVertex {
 struct VertexData {
   vec4 o[16];
 };
-layout(location = 1) in VertexData in_vtx[];
-layout(location = 1) out VertexData out_vtx;
+layout(location = 0) in VertexData in_vtx[];
+layout(location = 0) out VertexData out_vtx;
 
 layout(triangles) in;
 layout(triangle_strip, max_vertices = 6) out;