s390/compat: remove compat exec domain

The whole compat exec domain code doesn't make any difference.

From the registered s390_exec_domain:

- exec domain name is only displayed in /proc/execdomains
- handler is unused
- pers_low and pers_high are only used internally to find this specific
  exec domain otherwise the default exec domain will be used
- all other fields match the default exec domain

So let's get rid of this.
Reported-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/kernel/Makefile

@@ -47,9 +47,8 @@ obj-$(CONFIG_SCHED_BOOK)	+= topology.o
 obj-$(CONFIG_HIBERNATION)	+= suspend.o swsusp_asm64.o
 obj-$(CONFIG_AUDIT)		+= audit.o
 compat-obj-$(CONFIG_AUDIT)	+= compat_audit.o
-obj-$(CONFIG_COMPAT)		+= compat_linux.o compat_signal.o \
-					compat_wrapper.o compat_exec_domain.o \
-					$(compat-obj-y)
+obj-$(CONFIG_COMPAT)		+= compat_linux.o compat_signal.o
+obj-$(CONFIG_COMPAT)		+= compat_wrapper.o $(compat-obj-y)
 
 obj-$(CONFIG_STACKTRACE)	+= stacktrace.o
 obj-$(CONFIG_KPROBES)		+= kprobes.o

arch/s390/kernel/compat_exec_domain.c

-/*
- * Support for 32-bit Linux for S390 personality.
- *
- * Copyright IBM Corp. 2000
- * Author(s): Gerhard Tonn (ton@de.ibm.com)
- *
- *
- */
-
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/personality.h>
-#include <linux/sched.h>
-
-static struct exec_domain s390_exec_domain;
-
-static int __init s390_init (void)
-{
-	s390_exec_domain.name = "Linux/s390";
-	s390_exec_domain.handler = NULL;
-	s390_exec_domain.pers_low = PER_LINUX32;
-	s390_exec_domain.pers_high = PER_LINUX32;
-	s390_exec_domain.signal_map = default_exec_domain.signal_map;
-	s390_exec_domain.signal_invmap = default_exec_domain.signal_invmap;
-	register_exec_domain(&s390_exec_domain);
-	return 0;
-}
-
-__initcall(s390_init);