mpc85xx: reserve upper 1MB of RAM for WS-AP3825i

The bootpage for the second core is placed by U-Boot in the upper 128k
of syste-memory.

This could either be a reserved-area or deducted from the total
system-memory. As only the latter is parsed by the bootwrapper, reduce
the available system memory for linux in order to preserve the bootpage
from being overwritten.

Signed-off-by: David Bauer <[email protected]>

target/linux/mpc85xx/files/arch/powerpc/boot/dts/ws-ap3825i.dts

@@ -301,7 +301,8 @@
 	};
 
 	memory {
-		reg = <0x0 0x0 0x0 0x10000000>;
+		/* Reserve upper MB for second-core-bootpage */
+		reg = <0x0 0x0 0x0 0xff00000>;
 	};
 
 	soc@ffe00000 {