Documentation/: it's -> its where appropriate

Fix obvious cases of "it's" being used when "its" was meant.

Signed-off-by: Francis Galiegue <fgaliegue@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
index 79f533f..46d2210 100644
--- a/Documentation/powerpc/booting-without-of.txt
+++ b/Documentation/powerpc/booting-without-of.txt
@@ -1289,7 +1289,7 @@
 the interrupt tree.  The value of interrupt-parent is the
 phandle of the parent node.
 
-If the interrupt-parent property is not defined for a node, it's
+If the interrupt-parent property is not defined for a node, its
 interrupt parent is assumed to be an ancestor in the node's
 _device tree_ hierarchy.