remove unnamed union to please gcc-2.95

$OpenBSD: gcc2-patch-src_cairo-gl-private_h,v 1.1 2011/01/05 13:26:05 eric Exp $
--- src/cairo-gl-private.h.orig	Mon Jan  3 12:23:14 2011
+++ src/cairo-gl-private.h	Mon Jan  3 12:23:40 2011
@@ -142,7 +142,6 @@ typedef enum cairo_gl_var_type {
  */
 typedef struct cairo_gl_operand {
     cairo_gl_operand_type_t type;
-    union {
 	struct {
 	    GLuint tex;
 	    cairo_gl_surface_t *surface;
@@ -167,7 +166,6 @@ typedef struct cairo_gl_operand {
 	    float radius_1;
             cairo_extend_t extend;
 	} radial;
-    };
     unsigned int vertex_offset;
 } cairo_gl_operand_t;
 
