[NFC][OpenMP] Remove unused variable `new_iv_saved` in `openmp/runtime/src/kmp_collapse.cpp`

GitOrigin-RevId: 319d5d99cadfee2a4cd4985db98399b99fb213fd
diff --git a/runtime/src/kmp_collapse.cpp b/runtime/src/kmp_collapse.cpp
index cbfc525..8d0ed0e 100644
--- a/runtime/src/kmp_collapse.cpp
+++ b/runtime/src/kmp_collapse.cpp
@@ -1135,10 +1135,6 @@
   kmp_iterations_t iterations =
       (kmp_iterations_t)__kmp_allocate(sizeof(kmp_loop_nest_iv_t) * n);
 
-#if defined(KMP_DEBUG)
-  auto new_iv_saved = new_iv;
-#endif
-
   // First, calc corresponding iteration in every modified loop:
   for (kmp_index_t ind = n; ind > 0;) {
     --ind;