ARM: dts: am43xx-epos-evm: Don't use read/write wait monitoring

NAND uses wait pin only to indicate device readiness after
a block/page operation. It is not use to extend individual
read/write cycle and so read/write wait pin monitoring must
be disabled for NAND.

Add gpmc wait pin information as the NAND uses wait pin 0
for device ready indication.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Reviewed-by: Pekon Gupta <pekon@pek-sem.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am43x-epos-evm.dts

@@ -459,8 +459,7 @@
 		gpmc,access-ns = <30>; /* tCEA + 4*/
 		gpmc,rd-cycle-ns = <40>;
 		gpmc,wr-cycle-ns = <40>;
-		gpmc,wait-on-read = "true";
-		gpmc,wait-on-write = "true";
+		gpmc,wait-pin = <0>;
 		gpmc,bus-turnaround-ns = <0>;
 		gpmc,cycle2cycle-delay-ns = <0>;
 		gpmc,clk-activation-ns = <0>;