vulkan: Remove VkDescriptorSetLayoutChain from vkCmdBindDescriptorSets

This is part of r30446 on vulkan.h, discussed in bug 13632.

Meaty chunks of this commit done by Olv, basic hook up and testing by Cody.
diff --git a/layers/draw_state.cpp b/layers/draw_state.cpp
index 4d6620a..3510370 100644
--- a/layers/draw_state.cpp
+++ b/layers/draw_state.cpp
@@ -1997,7 +1997,7 @@
     nextTable.CmdBindDynamicStateObject(cmdBuffer, stateBindPoint, state);
 }
 
-VK_LAYER_EXPORT void VKAPI vkCmdBindDescriptorSets(VkCmdBuffer cmdBuffer, VkPipelineBindPoint pipelineBindPoint, VkDescriptorSetLayoutChain layoutChain, uint32_t layoutChainSlot, uint32_t count, const VkDescriptorSet* pDescriptorSets, const uint32_t* pUserData)
+VK_LAYER_EXPORT void VKAPI vkCmdBindDescriptorSets(VkCmdBuffer cmdBuffer, VkPipelineBindPoint pipelineBindPoint, uint32_t layoutChainSlot, uint32_t count, const VkDescriptorSet* pDescriptorSets, const uint32_t* pUserData)
 {
     GLOBAL_CB_NODE* pCB = getCBNode(cmdBuffer);
     if (pCB) {
@@ -2034,7 +2034,7 @@
         sprintf(str, "Attempt to use CmdBuffer %p that doesn't exist!", (void*)cmdBuffer);
         layerCbMsg(VK_DBG_MSG_ERROR, VK_VALIDATION_LEVEL_0, cmdBuffer, 0, DRAWSTATE_INVALID_CMD_BUFFER, "DS", str);
     }
-    nextTable.CmdBindDescriptorSets(cmdBuffer, pipelineBindPoint, layoutChain, layoutChainSlot, count, pDescriptorSets, pUserData);
+    nextTable.CmdBindDescriptorSets(cmdBuffer, pipelineBindPoint, layoutChainSlot, count, pDescriptorSets, pUserData);
 }
 
 VK_LAYER_EXPORT void VKAPI vkCmdBindIndexBuffer(VkCmdBuffer cmdBuffer, VkBuffer buffer, VkDeviceSize offset, VkIndexType indexType)