hush: fix EXIT trap display inside exit trap handler

function                                             old     new   delta
hush_exit                                             84      78      -6

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

shell/hush_test/hush-trap/exit.right

@@ -1,2 +1,12 @@
 cow
 moo
+Traps1:
+trap -- 'exitfunc' EXIT
+Traps2:
+trap -- 'echo Should not run' EXIT
+Check1: 42
+Traps1:
+trap -- 'exitfunc' EXIT
+Traps2:
+trap -- 'echo Should not run' EXIT
+Check2: 42