Fix typos in /Documentation : 'U-Z'

This patch fixes typos in various Documentation txts. The patch addresses some
+words starting with the letters 'U-Z'.

Looks like I made it through the alphabet...just in time to start over again
+too!  Maybe I can fit more profound fixes into the next round...?  Time will
+tell. :)

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/Documentation/uml/UserModeLinux-HOWTO.txt b/Documentation/uml/UserModeLinux-HOWTO.txt
index b60590e..628013f 100644
--- a/Documentation/uml/UserModeLinux-HOWTO.txt
+++ b/Documentation/uml/UserModeLinux-HOWTO.txt
@@ -1477,7 +1477,7 @@
 
 
 
-  Making it world-writeable looks bad, but it seems not to be
+  Making it world-writable looks bad, but it seems not to be
   exploitable as a security hole.  However, it does allow anyone to cre-
   ate useless tap devices (useless because they can't configure them),
   which is a DOS attack.  A somewhat more secure alternative would to be