Moved all references to file descriptors out of the generic object
structure.
Changed the poll()-related routines to deal with file descriptors
instead of objects and integrated poll support into fd.c.

diff --git a/server/hook.c b/server/hook.c
index b69b1cc..83b540b 100644
--- a/server/hook.c
+++ b/server/hook.c
@@ -79,7 +79,7 @@
     struct hook_table *table;
     int i;
 
-    if ((table = alloc_object( &hook_table_ops, -1 )))
+    if ((table = alloc_object( &hook_table_ops )))
     {
         for (i = 0; i < NB_HOOKS; i++)
         {