binding: rename descriptor region to descriptor pool

This should be trivial, except that the intel driver has intel_desc_pool
internally.  Exchange the names of intel_desc_pool and intel_desc_region.
diff --git a/include/xglDbg.h b/include/xglDbg.h
index be63828..7e655e6 100644
--- a/include/xglDbg.h
+++ b/include/xglDbg.h
@@ -91,10 +91,10 @@
     XGL_DBG_OBJECT_BUFFER,
     XGL_DBG_OBJECT_BUFFER_VIEW,
     XGL_DBG_OBJECT_DESCRIPTOR_SET_LAYOUT,
-    XGL_DBG_OBJECT_DESCRIPTOR_REGION,
+    XGL_DBG_OBJECT_DESCRIPTOR_POOL,
 
     XGL_DBG_OBJECT_TYPE_BEGIN_RANGE = XGL_DBG_OBJECT_UNKNOWN,
-    XGL_DBG_OBJECT_TYPE_END_RANGE   = XGL_DBG_OBJECT_DESCRIPTOR_REGION,
+    XGL_DBG_OBJECT_TYPE_END_RANGE   = XGL_DBG_OBJECT_DESCRIPTOR_POOL,
     XGL_NUM_DBG_OBJECT_TYPE         = (XGL_DBG_OBJECT_TYPE_END_RANGE - XGL_DBG_OBJECT_TYPE_BEGIN_RANGE + 1),
 } XGL_DBG_OBJECT_TYPE;