ACPI: thinkpad-acpi: bump up version to 0.18

The NVRAM polling support for hot keys is reason enough to
bump up the version string.  Do it.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
index 9ff9142..11ee444 100644
--- a/drivers/misc/thinkpad_acpi.c
+++ b/drivers/misc/thinkpad_acpi.c
@@ -21,7 +21,7 @@
  *  02110-1301, USA.
  */
 
-#define IBM_VERSION "0.17"
+#define IBM_VERSION "0.18"
 #define TPACPI_SYSFS_VERSION 0x020101
 
 /*