OpenGL: fix GPU_SHADER_TEXT on non-Mac

Developed on Mac and committed quickly.. oops

source/blender/gpu/shaders/gpu_shader_text_frag.glsl

@@ -1,14 +1,21 @@
 
-flat varying vec4 color;
-noperspective varying vec2 texcoord;
+#if __VERSION__ == 120
+  flat varying vec4 color;
+  noperspective varying vec2 texcoord;
+  #define fragColor gl_FragColor
+#else
+  flat in vec4 color;
+  noperspective in vec2 texcoord;
+  out vec4 fragColor;
+#endif
 
 uniform sampler2D glyph;
 
 void main()
 {
 	// input color replaces texture color
-	gl_FragColor.rgb = color.rgb;
+	fragColor.rgb = color.rgb;
 
 	// modulate input alpha & texture alpha
-	gl_FragColor.a = color.a * texture2D(glyph, texcoord).a;
+	fragColor.a = color.a * texture2D(glyph, texcoord).a;
 }

source/blender/gpu/shaders/gpu_shader_text_vert.glsl

@@ -1,11 +1,15 @@
 
 // TODO(merwin):
-// - use modern GLSL
 // - uniform color, not per vertex
 // - generic attrib inputs (2D pos, tex coord)
 
-flat varying vec4 color;
-noperspective varying vec2 texcoord;
+#if __VERSION__ == 120
+  flat varying vec4 color;
+  noperspective varying vec2 texcoord;
+#else
+  flat out vec4 color;
+  noperspective out vec2 texcoord;
+#endif
 
 void main()
 {