uml: throw out CONFIG_MODE_TT

This patchset throws out tt mode, which has been non-functional for a while.

This is done in phases, interspersed with code cleanups on the affected files.

The removal is done as follows:
	remove all code, config options, and files which depend on
CONFIG_MODE_TT
	get rid of the CHOOSE_MODE macro, which decided whether to
call tt-mode or skas-mode code, and replace invocations with their
skas portions
	replace all now-trivial procedures with their skas equivalents

There are now a bunch of now-redundant pieces of data structures, including
mode-specific pieces of the thread structure, pt_regs, and mm_context.  These
are all replaced with their skas-specific contents.

As part of the ongoing style compliance project, I made a style pass over all
files that were changed.  There are three such patches, one for each phase,
covering the files affected by that phase but no later ones.

I noticed that we weren't freeing the LDT state associated with a process when
it exited, so that's fixed in one of the later patches.

The last patch is a tidying patch which I've had for a while, but which caused
inexplicable crashes under tt mode.  Since that is no longer a problem, this
can now go in.

This patch:

Start getting rid of tt mode support.

This patch throws out CONFIG_MODE_TT and all config options, code, and files
which depend on it.

CONFIG_MODE_SKAS is gone and everything that depends on it is included
unconditionally.

The few changed lines are in re-written Kconfig help, lines which needed
something skas-related removed from them, and a few more which weren't
strictly deletions.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index d870905..4d563b9 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -735,8 +735,6 @@
 }
 #endif
 
-#ifdef CONFIG_MODE_SKAS
-
 static void stack_proc(void *arg)
 {
 	struct task_struct *from = current, *to = arg;
@@ -750,7 +748,7 @@
  *  Dumps a stacks registers to the linux console.
  *  Usage stack <pid>.
  */
-static void do_stack_trace(struct mc_request *req)
+void mconsole_stack(struct mc_request *req)
 {
 	char *ptr = req->request.data;
 	int pid_requested= -1;
@@ -781,17 +779,6 @@
 	}
 	with_console(req, stack_proc, to);
 }
-#endif /* CONFIG_MODE_SKAS */
-
-void mconsole_stack(struct mc_request *req)
-{
-	/* This command doesn't work in TT mode, so let's check and then
-	 * get out of here
-	 */
-	CHOOSE_MODE(mconsole_reply(req, "Sorry, this doesn't work in TT mode",
-				   1, 0),
-		    do_stack_trace(req));
-}
 
 /* Changed by mconsole_setup, which is __setup, and called before SMP is
  * active.