Fix build with GCC 2.95.

src/glx/x11/glx_pbuffer.c

@@ -220,14 +220,14 @@ GetDrawableAttribute(Display * dpy, GLXDrawable drawable,
    unsigned int length;
    unsigned int i;
    unsigned int num_attributes;
+   GLboolean use_glx_1_3;
 
    if ((dpy == NULL) || (drawable == 0)) {
       return 0;
    }
 
    priv = __glXInitialize(dpy);
-   GLboolean use_glx_1_3 = ((priv->majorVersion > 1)
-                            || (priv->minorVersion >= 3));
+   use_glx_1_3 = ((priv->majorVersion > 1) || (priv->minorVersion >= 3));
 
    *value = 0;