Input: i8042 - add Thinkpad R31 to nomux list

Thinkpad R31 needs i8042 nomux quirk.  Stops jittery jumping mouse
and random keyboard input. Fixes kernel bug #11723.  Cherry picked
from Ubuntu who have sometimes (on-again-off-again) had a fix in
their patched kernels.
Signed-off-by: Colin B Macdonald <cbm@m.fsf.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/serio/i8042-x86ia64io.h

@@ -322,6 +322,13 @@ static struct dmi_system_id __initdata i8042_dmi_nomux_table[] = {
 			DMI_MATCH(DMI_PRODUCT_NAME, "N34AS6"),
 		},
 	},
+	{
+		.ident = "IBM 2656",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "2656"),
+		},
+	},
 	{ }
 };