x86/entry: Remove SCHEDULE_USER and asm/context-tracking.h

SCHEDULE_USER is no longer used, and asm/context-tracking.h
contained nothing else.  Remove the header entirely.
Signed-off-by: NAndy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/854e9b45f69af20e26c47099eb236321563ebcee.1435952415.git.luto@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

arch/x86/entry/entry_64.S

@@ -33,7 +33,6 @@
 #include <asm/paravirt.h>
 #include <asm/percpu.h>
 #include <asm/asm.h>
-#include <asm/context_tracking.h>
 #include <asm/smap.h>
 #include <asm/pgtable_types.h>
 #include <linux/err.h>

arch/x86/include/asm/context_tracking.h

-#ifndef _ASM_X86_CONTEXT_TRACKING_H
-#define _ASM_X86_CONTEXT_TRACKING_H
-
-#ifdef CONFIG_CONTEXT_TRACKING
-# define SCHEDULE_USER call schedule_user
-#else
-# define SCHEDULE_USER call schedule
-#endif
-
-#endif