update to the latest vertex fetch proposal

The main difference is that XGL_SLOT_VERTEX_INPUT is replaced by
xglCmdBindVertexData.  This actually simplifies the driver, which can be seen
with:

 $ git show icd/intel/

The new proposal also adds some new formats, but they are ignored for now
because they are marked TBD.
diff --git a/loader/loader.c b/loader/loader.c
index 6bfba28..3f8efdb 100644
--- a/loader/loader.c
+++ b/loader/loader.c
@@ -525,6 +525,7 @@
     tab->CmdBindStateObject = fpGPA(gpu, (const XGL_CHAR *) "xglCmdBindStateObject");
     tab->CmdBindDescriptorSet = fpGPA(gpu, (const XGL_CHAR *) "xglCmdBindDescriptorSet");
     tab->CmdBindDynamicMemoryView = fpGPA(gpu, (const XGL_CHAR *) "xglCmdBindDynamicMemoryView");
+    tab->CmdBindVertexData = fpGPA(gpu, (const XGL_CHAR *) "xglCmdBindVertexData");
     tab->CmdBindIndexData = fpGPA(gpu, (const XGL_CHAR *) "xglCmdBindIndexData");
     tab->CmdBindAttachments = fpGPA(gpu, (const XGL_CHAR *) "xglCmdBindAttachments");
     tab->CmdPrepareMemoryRegions = fpGPA(gpu, (const XGL_CHAR *) "xglCmdPrepareMemoryRegions");
@@ -980,6 +981,8 @@
         return disp_table->CmdBindDescriptorSet;
     else if (!strncmp("xglCmdBindDynamicMemoryView", (const char *) pName, sizeof ("xglCmdBindDynamicMemoryView")))
         return disp_table->CmdBindDynamicMemoryView;
+    else if (!strncmp("xglCmdBindVertexData", (const char *) pName, sizeof ("xglCmdBindVertexData")))
+        return disp_table->CmdBindVertexData;
     else if (!strncmp("xglCmdBindIndexData", (const char *) pName, sizeof ("xglCmdBindIndexData")))
         return disp_table->CmdBindIndexData;
     else if (!strncmp("xglCmdBindAttachments", (const char *) pName, sizeof ("xglCmdBindAttachments")))