mn10300: get rid of set_fs(USER_DS) in sigframe setup

It really has no business being there; short of a serious kernel bug
we should already have USER_DS at that point.  It shouldn't have been
done on x86 either...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/mn10300/kernel/signal.c

@@ -333,8 +333,6 @@ static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
 	regs->d0 = sig;
 	regs->d1 = (unsigned long) &frame->sc;
 
-	set_fs(USER_DS);
-
 	/* the tracer may want to single-step inside the handler */
 	if (test_thread_flag(TIF_SINGLESTEP))
 		ptrace_notify(SIGTRAP);
@@ -416,8 +414,6 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	regs->d0 = sig;
 	regs->d1 = (long) &frame->info;
 
-	set_fs(USER_DS);
-
 	/* the tracer may want to single-step inside the handler */
 	if (test_thread_flag(TIF_SINGLESTEP))
 		ptrace_notify(SIGTRAP);