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/networking/ifenslave.c b/Documentation/networking/ifenslave.c
index 1b96ccd..2bac961 100644
--- a/Documentation/networking/ifenslave.c
+++ b/Documentation/networking/ifenslave.c
@@ -756,7 +756,7 @@
 		 */
 		if (abi_ver < 1) {
 			/* For old ABI, the master needs to be
-			 * down before setting it's hwaddr
+			 * down before setting its hwaddr
 			 */
 			res = set_if_down(master_ifname, master_flags.ifr_flags);
 			if (res) {