thinkpad-acpi: bump up version to 0.23

Plenty of high-profile changes, so it deserves a new version number.

Features added since 0.22:
 *  Restrict unsafe LEDs
 *  New race-less brightness control strategy for IBM ThinkPads
 *  Disclose TGID of driver access from userspace (debug)
 *  Warn when deprecated functions are used

Other changes:
 *  Better debug messages in some subdrivers
 *  Removed "hotkey disable" support, since it breaks the driver
 *  Dropped "ibm-acpi" alias

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt
index 3d76507..e7e9a690 100644
--- a/Documentation/laptops/thinkpad-acpi.txt
+++ b/Documentation/laptops/thinkpad-acpi.txt
@@ -1,7 +1,7 @@
 		     ThinkPad ACPI Extras Driver
 
-                            Version 0.22
-                        November 23rd,  2008
+                            Version 0.23
+                          April 10th, 2009
 
                Borislav Deianov <borislav@users.sf.net>
              Henrique de Moraes Holschuh <hmh@hmh.eng.br>