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/power/regulator/machine.txt b/Documentation/power/regulator/machine.txt
index 63728fe..bdec39b 100644
--- a/Documentation/power/regulator/machine.txt
+++ b/Documentation/power/regulator/machine.txt
@@ -52,7 +52,7 @@
 };
 
 Regulator-1 supplies power to Regulator-2. This relationship must be registered
-with the core so that Regulator-1 is also enabled when Consumer A enables it's
+with the core so that Regulator-1 is also enabled when Consumer A enables its
 supply (Regulator-2). The supply regulator is set by the supply_regulator_dev
 field below:-