classmate-laptop: Fix extra keys hardware id.

Since ACPI devices ids were changed to use always upper-case letters, the ACPI
id of the extra keys (FNBT0000) was not maching the one defined in the driver
(FnBT0000), causing the extra keys not to work.

The patch replaces the driver id with the one reported by ACPI, fixing the
problem.
Signed-off-by: Miguel Gómez <magomez@igalia.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

drivers/platform/x86/classmate-laptop.c

@@ -45,7 +45,7 @@ struct cmpc_accel {
 #define CMPC_ACCEL_HID_V4	"ACCE0001"
 #define CMPC_TABLET_HID		"TBLT0000"
 #define CMPC_IPML_HID	"IPML200"
-#define CMPC_KEYS_HID		"FnBT0000"
+#define CMPC_KEYS_HID		"FNBT0000"
 
 /*
  * Generic input device code.