; Remove an obsolete comment

* src/editfns.c (Ftranspose_regions): Remove an obsolete comment about
  memmove, following up to commit 72af86bd8c of 8 Jul 2010 by Andreas
  Schwab and commit 354f9f0fc6 of 23 Feb 2016 by Fredrik Bergroth,
  both of which added calls to memmove.

src/editfns.c

@@ -4265,9 +4265,6 @@ ring.  */)
      enough to use as the temporary storage?  That would avoid an
      allocation... interesting.  Later, don't fool with it now.  */
 
-  /* Working without memmove, for portability (sigh), so must be
-     careful of overlapping subsections of the array...  */
-
   if (end1 == start2)		/* adjacent regions */
     {
       modify_text (start1, end2);