Prevent stdin, stdout and stderr definitions clash.

Use uint64 instead of uint for sizes, and use casts where needed
(upstream 0cf804a8666404444968c995b03fe8af9893a58f)

From openSUSE:
Make xauth do not cause DNS lookups. This can slow down things, so we
use nlist instead of list.
Also pass -q, just to be sure we don't unsolicited output.

diff -ur a/libgksu/gksu-process.c b/libgksu/gksu-process.c
--- a/libgksu/gksu-process.c	2010-09-09 16:01:08.000000000 +0300
+++ b/libgksu/gksu-process.c	2013-12-24 12:50:37.876813177 +0200
@@ -62,7 +62,7 @@
    * application decides to close an FD we also keep a 'mirror'
    * GIOChannel for its side of the pipe, so that we can monitor the
    * application closing an FD, for instance */
-  gint stdin[2];
+  gint gksu_stdin[2];
   GIOChannel *stdin_channel;
   guint stdin_source_id;
   GIOChannel *stdin_mirror;
@@ -73,13 +73,13 @@
    * because the buffer is filled, and application needs to read some
    * of it; we need to give it a chance to read the buffer, thus, but
    * still need to remember to write what is left */
-  gint stdout[2];
+  gint gksu_stdout[2];
   GIOChannel *stdout_channel;
   GIOChannel *stdout_mirror;
   guint stdout_mirror_id;
   GksuWriteQueue *stdout_write_queue;
 
-  gint stderr[2];
+  gint gksu_stderr[2];
   GIOChannel *stderr_channel;
   GIOChannel *stderr_mirror;
   guint stderr_mirror_id;
@@ -337,8 +337,8 @@
     }
 
   /* get the authorization token */
-  tmp = g_strdup_printf ("%s -i list %s | "
-			 "head -1 | awk '{ print $3 }'",
+  tmp = g_strdup_printf ("%s -q -i nlist %s | "
+			 "head -1 | awk '{ print $9 }'",
 			 xauth_bin,
 			 display);
   if ((xauth_output = popen (tmp, "r")) == NULL)
@@ -651,7 +651,7 @@
     {
       gksu_process_prepare_pipe(&(priv->stdin_channel),
                                 &(priv->stdin_mirror),
-                                priv->stdin,
+                                priv->gksu_stdin,
                                 standard_input,
                                 TRUE);
 
@@ -671,7 +671,7 @@
     {
       gksu_process_prepare_pipe(&(priv->stdout_channel),
                                 &(priv->stdout_mirror),
-                                priv->stdout,
+                                priv->gksu_stdout,
                                 standard_output,
                                 FALSE);
 
@@ -688,7 +688,7 @@
     {
       gksu_process_prepare_pipe(&(priv->stderr_channel),
                                 &(priv->stderr_mirror),
-                                priv->stderr,
+                                priv->gksu_stderr,
                                 standard_error,
                                 FALSE);