sparc32: Fix exit flag passed from traced sys_sigreturn

Pass 1 in %o1 to indicate that syscall_trace accounts exit.
Signed-off-by: NKirill Tkhai <tkhai@yandex.ru>
CC: David Miller <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/sparc/kernel/entry.S

@@ -839,7 +839,7 @@ sys_sigreturn:
 	 nop
 
 	call	syscall_trace
-	 nop
+	 mov	1, %o1
 
 1:
 	/* We don't want to muck with user registers like a