drivers/char/i8k.c: add Dell XPLS L421X

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=60772

Signed-off-by: Alan Cox <alan@linux.intel.com>
Reported-by: Leho Kraav <leho@kraav.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/char/i8k.c b/drivers/char/i8k.c
index 40cc0cf2..e6939e1 100644
--- a/drivers/char/i8k.c
+++ b/drivers/char/i8k.c
@@ -664,6 +664,13 @@
 			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
 		},
 	},
+	{
+		.ident = "Dell XPS421",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
+		},
+	},
         { }
 };