ARM: dts: aspeed: tacoma: Use 64MB for firmware memory

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Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Joel Stanley <joel@jms.id.au>

arch/arm/boot/dts/aspeed-bmc-opp-tacoma.dts

@@ -27,7 +27,7 @@ reserved-memory {
 
 		flash_memory: region@ba000000 {
 			no-map;
-			reg = <0xba000000 0x2000000>; /* 32M */
+			reg = <0xb8000000 0x4000000>; /* 64M */
 		};
 	};