drd: Remove drd/drd_list.h again because of its GPLv2 license.

For more info about Valgrind source code licensing, see also:
[1] Top level README line 51.
[2] http://valgrind.org/docs/manual/manual-intro.html#manual-intro.overview, last paragraph.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@12356 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/drd/drd_segment.h b/drd/drd_segment.h
index 5782b4a..1df257f 100644
--- a/drd/drd_segment.h
+++ b/drd/drd_segment.h
@@ -33,7 +33,6 @@
  */
 
 
-#include "drd_list.h"
 #include "drd_vc.h"
 #include "pub_drd_bitmap.h"
 #include "pub_tool_execontext.h" // ExeContext
@@ -42,9 +41,11 @@
 
 typedef struct segment
 {
-   struct list_head   g_list;
+   struct segment*    g_next;
+   struct segment*    g_prev;
    /** Pointers to next and previous segments executed by the same thread. */
-   struct list_head   thr_list;
+   struct segment*    thr_next;
+   struct segment*    thr_prev;
    DrdThreadId        tid;
    /** Reference count: number of pointers that point to this segment. */
    int                refcnt;
@@ -59,7 +60,7 @@
    struct bitmap      bm;
 } Segment;
 
-extern struct list_head DRD_(g_sg_list);
+extern Segment* DRD_(g_sg_list);
 
 Segment* DRD_(sg_new)(const DrdThreadId creator, const DrdThreadId created);
 static int DRD_(sg_get_refcnt)(const Segment* const sg);