ash: fix $! value when traps are set

Signed-off-by: Alexander Shishkin <virtuoso@slind.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/shell/ash.c b/shell/ash.c
index fd119fa..988edab 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -4633,6 +4633,7 @@
 			INT_ON;
 		}
 	}
+	may_have_traps = 0;
 }
 
 /* Lives far away from here, needed for forkchild */