[libcxxabi] Fix printf formats in a test.

[simon_tatham]

Summary

This is the libcxxabi counterpart of D89545, and would have been part
of that patch if I'd spotted it soon enough (oops). One test in
libcxxabi is using the %lu printf format to refer to size_t, which
should be %zu.

libcxxabi/test/test_fallback_malloc.pass.cpp

 void exhaustion_test1 () {
     container ptrs;
 
     init_heap ();
     std::printf("Constant exhaustion tests\n");
 
 //  Delete in allocation order
     ptrs = alloc_series ( 32 );
-    std::printf("Allocated %lu 32 byte chunks\n", ptrs.size());
+    std::printf("Allocated %zu 32 byte chunks\n", ptrs.size());
     print_free_list ();
     for ( container::iterator iter = ptrs.begin (); iter != ptrs.end (); ++iter )
         fallback_free ( *iter );
     print_free_list ();
     std::printf("----\n");
 
 //  Delete in reverse order
     ptrs = alloc_series ( 32 );
-    std::printf("Allocated %lu 32 byte chunks\n", ptrs.size());
+    std::printf("Allocated %zu 32 byte chunks\n", ptrs.size());
     for ( container::reverse_iterator iter = ptrs.rbegin (); iter != ptrs.rend (); ++iter )
         fallback_free ( *iter );
     print_free_list ();
     std::printf("----\n");
 
 //  Alternate deletions
     ptrs = alloc_series ( 32 );
-    std::printf("Allocated %lu 32 byte chunks\n", ptrs.size());
+    std::printf("Allocated %zu 32 byte chunks\n", ptrs.size());
     while ( ptrs.size () > 0 )
         fallback_free ( pop ( ptrs, ptrs.size () % 1 == 1 ));
     print_free_list ();
 }
 
 void exhaustion_test2 () {
     container ptrs;
     init_heap ();
 
     std::printf("Growing exhaustion tests\n");
 
 //  Delete in allocation order
     ptrs = alloc_series ( 32, 1.5 );
 
-    std::printf("Allocated %lu { 32, 48, 72, 108, 162 ... } byte chunks\n", ptrs.size());
+    std::printf("Allocated %zu { 32, 48, 72, 108, 162 ... } byte chunks\n",
+                ptrs.size());
     print_free_list ();
     for ( container::iterator iter = ptrs.begin (); iter != ptrs.end (); ++iter )
         fallback_free ( *iter );
     print_free_list ();
     std::printf("----\n");
 
 //  Delete in reverse order
     print_free_list ();
     ptrs = alloc_series ( 32, 1.5 );
-    std::printf("Allocated %lu { 32, 48, 72, 108, 162 ... } byte chunks\n", ptrs.size());
+    std::printf("Allocated %zu { 32, 48, 72, 108, 162 ... } byte chunks\n",
+                ptrs.size());
     for ( container::reverse_iterator iter = ptrs.rbegin (); iter != ptrs.rend (); ++iter )
         fallback_free ( *iter );
     print_free_list ();
     std::printf("----\n");
 
 //  Alternate deletions
     ptrs = alloc_series ( 32, 1.5 );
-    std::printf("Allocated %lu { 32, 48, 72, 108, 162 ... } byte chunks\n", ptrs.size());
+    std::printf("Allocated %zu { 32, 48, 72, 108, 162 ... } byte chunks\n",
+                ptrs.size());
     while ( ptrs.size () > 0 )
         fallback_free ( pop ( ptrs, ptrs.size () % 1 == 1 ));
     print_free_list ();
 
 }
 
 void exhaustion_test3 () {
     const size_t allocs [] = { 124, 60, 252, 60, 4 };
     container ptrs;
     init_heap ();
 
     std::printf("Complete exhaustion tests\n");
 
 //  Delete in allocation order
     ptrs = alloc_series ( allocs, sizeof ( allocs ) / sizeof ( allocs[0] ));
-    std::printf("Allocated %lu chunks\n", ptrs.size());
+    std::printf("Allocated %zu chunks\n", ptrs.size());
     print_free_list ();
     for ( container::iterator iter = ptrs.begin (); iter != ptrs.end (); ++iter )
         fallback_free ( *iter );
     print_free_list ();
     std::printf("----\n");
 
 //  Delete in reverse order
     print_free_list ();
     ptrs = alloc_series ( allocs, sizeof ( allocs ) / sizeof ( allocs[0] ));
-    std::printf("Allocated %lu chunks\n", ptrs.size());
+    std::printf("Allocated %zu chunks\n", ptrs.size());
     for ( container::reverse_iterator iter = ptrs.rbegin (); iter != ptrs.rend (); ++iter )
         fallback_free ( *iter );
     print_free_list ();
     std::printf("----\n");
 
 //  Alternate deletions
     ptrs = alloc_series ( allocs, sizeof ( allocs ) / sizeof ( allocs[0] ));
-    std::printf("Allocated %lu chunks\n", ptrs.size());
+    std::printf("Allocated %zu chunks\n", ptrs.size());
     while ( ptrs.size () > 0 )
         fallback_free ( pop ( ptrs, ptrs.size () % 1 == 1 ));
     print_free_list ();
 
 }
 
 
 int main () {