Fix "can not" in Documentation and Kconfig

Randy brought it to my attention that in proper english "can not" should always
be written "cannot". I donot see any reason to argue, even if I mightnot
understand why this rule exists.  This patch fixes "can not" in several
Documentation files as well as three Kconfigs.

Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

Documentation/uml/UserModeLinux-HOWTO.txt

@@ -3972,7 +3972,7 @@
   nneett
 
   If you can connect to the host, and the host can connect to UML, but
-  you can not connect to any other machines, then you may need to enable
+  you cannot connect to any other machines, then you may need to enable
   IP Masquerading on the host.  Usually this is only experienced when
   using private IP addresses (192.168.x.x or 10.x.x.x) for host/UML
   networking, rather than the public address space that your host is