libxl: fix gfx_passthrough config option (including dropped hunk)

libxl: fix gfx_passthrough config option (including dropped hunk)

Add the missing hunk from 22711:4f6fee3a456e (fixed up for intervening
movement of dm info) to actually pass the -gfx_passthru argument to
qemu.

Also change the idl comment for the gfx_passthrough config setting to
that from Sergey.

Author: Sergey Tovpeko <tovpeko@altell.ru>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
diff -r c281e9c58146 -r 9108ce3fc62c tools/libxl/libxl.idl
--- a/tools/libxl/libxl.idl	Mon Jan 17 17:31:24 2011 +0000
+++ b/tools/libxl/libxl.idl	Mon Jan 17 17:43:22 2011 +0000
@@ -152,7 +152,7 @@ libxl_device_model_info = Struct("device
     ("sdl",              bool,              False, "sdl enabled or disabled"),
     ("opengl",           bool,              False, "opengl enabled or disabled (if enabled requires sdl enabled)"),
     ("nographic",        bool,              False, "no graphics, use serial port"),
-    ("gfx_passthru",     bool,              False, "disable qemu graphics for PCI passthru of GPU from host"),
+    ("gfx_passthru",     bool,              False, "graphics passthrough enabled or disabled"),
     ("serial",           string,            False, "serial port re-direct to pty deivce"),
     ("boot",             string,            False, "boot order, for example dca"),
     ("usb",              bool,              False, "usb support enabled or disabled"),
diff -r c281e9c58146 -r 9108ce3fc62c tools/libxl/xl_cmdimpl.c
--- a/tools/libxl/xl_cmdimpl.c	Mon Jan 17 17:31:24 2011 +0000
+++ b/tools/libxl/xl_cmdimpl.c	Mon Jan 17 17:43:22 2011 +0000
@@ -682,6 +682,9 @@ static void parse_config_data(const char
         b_info->video_memkb = l * 1024;

     xlu_cfg_replace_string (config, "kernel", &b_info->kernel.path);
+
+    if (!xlu_cfg_get_long (config, "gfx_passthru", &l))
+        b_info->gfx_passthru = l;

     if (c_info->hvm == 1) {
         if (!xlu_cfg_get_long (config, "pae", &l))