of: fix a few typos in the binding documentation

Signed-off-by: Uwe Kleine-König <[e-mail]>
[rob herring: drop conflicting atmel-nand.txt changes]
Signed-off-by: Rob Herring <[e-mail]>

Documentation/devicetree/bindings/mtd/partition.txt

···
 	uimage@100000 {
 		reg = <0x0100000 0x200000>;
 	};
-];
+};