binding: update for pImmutableSamplers

v2: fix a typo in the type of shared_immutable_sampler (olv)
diff --git a/include/xgl.h b/include/xgl.h
index 78c0faa..f90b8a7 100644
--- a/include/xgl.h
+++ b/include/xgl.h
@@ -1824,7 +1824,7 @@
     XGL_DESCRIPTOR_TYPE                     descriptorType;
     uint32_t                                count;
     XGL_FLAGS                               stageFlags;         // XGL_SHADER_STAGE_FLAGS
-    XGL_SAMPLER                             immutableSampler;
+    const XGL_SAMPLER*                      pImmutableSamplers;
 } XGL_DESCRIPTOR_SET_LAYOUT_BINDING;
 
 typedef struct _XGL_DESCRIPTOR_SET_LAYOUT_CREATE_INFO
diff --git a/tests/xglrenderframework.cpp b/tests/xglrenderframework.cpp
index 005ef71..f5788b5 100644
--- a/tests/xglrenderframework.cpp
+++ b/tests/xglrenderframework.cpp
@@ -340,7 +340,7 @@
         bindings[i].descriptorType = m_type_counts[i].type;
         bindings[i].count = m_type_counts[i].count;
         bindings[i].stageFlags = XGL_SHADER_STAGE_FLAGS_ALL;
-        bindings[i].immutableSampler = XGL_NULL_HANDLE;
+        bindings[i].pImmutableSamplers = NULL;
     }
 
     // create XGL_DESCRIPTOR_SET_LAYOUT