arm64: tegra: Redefine force recovery key on Jetson AGX Xavier

The current BTN_1 code associated with the force-recovery key is not a
valid code for EV_KEY type input devices. This causes errors in the
libinput debug-events command.

There is no system level action that maps to the force-recovery key on
Jetson AGX Xavier, so assign it the KEY_SLEEP action, which at least
makes it do something marginally useful.
Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm64/boot/dts/nvidia/tegra194-p2972-0000.dts

@@ -152,7 +152,7 @@ force-recovery {
 			gpios = <&gpio TEGRA194_MAIN_GPIO(G, 0)
 				       GPIO_ACTIVE_LOW>;
 			linux,input-type = <EV_KEY>;
-			linux,code = <BTN_1>;
+			linux,code = <KEY_SLEEP>;
 			debounce-interval = <10>;
 		};