Move welcome text to correct subdirectory

They are right now being used by both triangles (if startup music is beatmap) and circles

osu.Game.Resources/Shaders/sh_CursorTrail.vs

@@ -1,12 +1,14 @@
 attribute vec2 m_Position;
 attribute vec4 m_Colour;
 attribute vec2 m_TexCoord;
+attribute vec4 m_TexRect;
 attribute float m_Time;
 
 varying vec2 v_DrawingPosition;
 varying vec2 v_MaskingPosition;
 varying vec4 v_Colour;
 varying vec2 v_TexCoord;
+varying vec4 v_TexRect;
 
 uniform mat4 g_ProjMatrix;
 uniform mat3 g_ToMaskingSpace;
@@ -27,5 +29,7 @@ void main(void)
     v_Colour = vec4(m_Colour.rgb, m_Colour.a * pow(clamp(m_Time - g_FadeClock, 0.0, 1.0), 1.7));
      
     v_TexCoord = m_TexCoord;
+    v_TexRect = m_TexRect;
+    
     gl_Position = g_ProjMatrix * vec4(m_Position, 1.0, 1.0);
 }