arc: Remove signal translation and exec_domain

As execution domain support is gone we can remove
signal translation from the signal code and remove
exec_domain from thread_info.

Signed-off-by: Richard Weinberger <[e-mail]>

arch/arc/include/asm/thread_info.h

···
 	int preempt_count;		/* 0 => preemptable, <0 => BUG */
 	struct task_struct *task;	/* main task structure */
 	mm_segment_t addr_limit;	/* thread address space */
-	struct exec_domain *exec_domain;/* execution domain */
 	__u32 cpu;			/* current CPU */
 	unsigned long thr_ptr;		/* TLS ptr */
 };
···
 #define INIT_THREAD_INFO(tsk)			\
 {						\
 	.task       = &tsk,			\
-	.exec_domain    = &default_exec_domain,	\
 	.flags      = 0,			\
 	.cpu        = 0,			\
 	.preempt_count  = INIT_PREEMPT_COUNT,	\

arch/arc/kernel/signal.c

···
 	return frame;
 }
 
-/*
- * translate the signal
- */
-static inline int map_sig(int sig)
-{
-	struct thread_info *thread = current_thread_info();
-	if (thread->exec_domain && thread->exec_domain->signal_invmap
-	    && sig < 32)
-		sig = thread->exec_domain->signal_invmap[sig];
-	return sig;
-}
-
 static int
 setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs)
 {
···
 		return err;
 
 	/* #1 arg to the user Signal handler */
-	regs->r0 = map_sig(ksig->sig);
+	regs->r0 = ksig->sig;
 
 	/* setup PC of user space signal handler */
 	regs->ret = (unsigned long)ksig->ka.sa.sa_handler;