[PRISM] pm_compile_logical: Fix OrNode in IfNode predicate

Fixes: https://github.com/ruby/prism/issues/2294

prism_compile.c

@@ -495,7 +495,9 @@ pm_compile_logical(rb_iseq_t *iseq, LINK_ANCHOR *const ret, pm_node_t *cond,
             return;
     }
     if (!label->refcnt) {
-        PM_PUTNIL;
+        if (popped) {
+            PM_PUTNIL;
+        }
     }
     else {
         ADD_LABEL(seq, label);

test/ruby/test_compile_prism.rb

@@ -1011,6 +1011,7 @@ module Prism
       assert_prism_eval('if ..1; end')
       assert_prism_eval('if 1..; end')
       assert_prism_eval('if 1..2; end')
+      assert_prism_eval('if true or true; end');
     end
 
     def test_OrNode