Fix an out-of-date comment

It still said that our tight compaction algorithm was _not_ order
preserving, but that hasn't been true for a long time; it _is_ order
preserving now.

Enclave/OblivAlgs/TightCompaction_v2.tcc

@@ -4,15 +4,18 @@
 #include "pthread.h"
 
 /*
-   TightCompaction (Non-Order Preserving Tight Compaction):
+   TightCompaction (Order Preserving Tight Compaction):
 
-   Non-Order Preserving TightCompaction can take an input array of blocks of
+   Order Preserving TightCompaction can take an input array of blocks of
    block_size bytes each, and an array of "marked" elements with ones at the
    indices corresponding to the blocks that need to be compacted.
    It returns the input array TightCompact-ed, i.e. all the real blocks are
    moved to the start of the array, or compacted to an input index
    (with wraparound)
 
+   This is the Oblivious Recusrive Compaction (ORCompact) algorithm from
+   our CCS 2022 paper "Fast Fully Oblivious Compaction and Shuffling".
+
  */
 
 template <OSwap_Style oswap_style>