ARM: dts: at91: sama7g5ek: fix debounce delay property for shdwc

There is no atmel,shdwc-debouncer property for SHDWC. The right DT property
is debounce-delay-us. Use it.

Fixes: 16b161bc ("ARM: dts: at91: sama7g5: add shdwc node")
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20230523052750.184223-1-claudiu.beznea@microchip.com

arch/arm/boot/dts/at91-sama7g5ek.dts

@@ -792,7 +792,7 @@ &sdmmc2 {
 };
 
 &shdwc {
-	atmel,shdwc-debouncer = <976>;
+	debounce-delay-us = <976>;
 	status = "okay";
 
 	input@0 {