ARM: shmobile: lager: correct memory map

The base address of the second memory region on the lager
board is 0x140000000. Update the tag used in the dts file accordingly.

This is a documentation fix and should have no run-time affect.

This problem was introduced when the second memory region
was added to the lager dts file by 62bc32a2
("ARM: shmobile: Include all 4 GiB of memory on Lager)"
in v3.14.
Reported-by: NNAOYA SHIIBA <naoya.shiiba.nx@renesas.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7790-lager.dts

@@ -32,7 +32,7 @@
 		reg = <0 0x40000000 0 0x40000000>;
 	};
 
-	memory@180000000 {
+	memory@140000000 {
 		device_type = "memory";
 		reg = <1 0x40000000 0 0xc0000000>;
 	};