sparc32: signal: Fix stack trampoline for RT signals

The stack trampoline generated by the sparc32 native version of
setup_rt_frame() calls sigreturn(), not rt_sigreturn().  This will
crash the task if it's ever used.  (glibc sets its own restorer, so
was not affected.)

The sparc64 compat implementation has the right syscall number.

This is untested; I have no way to run a sparc32 kernel.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/kernel/signal_32.c

@@ -401,8 +401,8 @@ static int setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs,
 	else {
 		regs->u_regs[UREG_I7] = (unsigned long)(&(sf->insns[0]) - 2);
 
-		/* mov __NR_sigreturn, %g1 */
-		err |= __put_user(0x821020d8, &sf->insns[0]);
+		/* mov __NR_rt_sigreturn, %g1 */
+		err |= __put_user(0x82102065, &sf->insns[0]);
 
 		/* t 0x10 */
 		err |= __put_user(0x91d02010, &sf->insns[1]);