[PATCH] uml: arch Kconfig menu cleanups

*) mark as "EXPERIMENTAL" various items that either aren't very stable or
   that are actively crashing the setup of users which don't really need them
   (i.e.  HIGHMEM and 3-level pagetables on x86 - nobody needs either,
   everybody reports "I'm using it and getting trouble").

*) move net/Kconfig near to the rest of network configurations, and
   drivers/block/Kconfig near "Block layer" submenu.

*) it's useless and doesn't work well to force NETDEVICES on and to disable
   the prompt like it's done.  Better remove the attempt, and change that to a
   simple "default y if UML".

*) drop the warning about "report problems about HPPFS" - it's redundant
   anyway, as that's the usual procedure, and HPPFS users are especially
   technical (i.e.  they know reporting bugs is _good_).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>