nios2: restarts apply only to the first sigframe we build...

stable inclusion
from stable-v5.10.138
commit 600ff4b13b0ecb94e7ba21531c7386074cca56ea
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60QFD

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=600ff4b13b0ecb94e7ba21531c7386074cca56ea

--------------------------------

commit 411a76b7 upstream.

Fixes: b53e906d ("nios2: Signal handling support")
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDinh Nguyen <dinguyen@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>

arch/nios2/kernel/signal.c

@@ -264,6 +264,7 @@ static int do_signal(struct pt_regs *regs)
 			regs->ea = restart_addr;
 			break;
 		}
+		regs->orig_r2 = -1;
 	}
 
 	if (get_signal(&ksig)) {