intel: add support for FF vertex fetch

shaderEntityIndex is used to index pVertexBindingDescriptions instead of
pVertexAttributeDescriptions.  Not really sure how that works.

https://cvs.khronos.org/bugzilla/show_bug.cgi?id=12774#c26
diff --git a/icd/intel/pipeline_shader.c b/icd/intel/pipeline_shader.c
index 9215df7..4d9b285 100644
--- a/icd/intel/pipeline_shader.c
+++ b/icd/intel/pipeline_shader.c
@@ -35,6 +35,7 @@
     const XGL_UINT resource_offset = rmap->rt_count;
     const XGL_UINT uav_offset = resource_offset + rmap->resource_count;
     const XGL_UINT sampler_offset = uav_offset + rmap->uav_count;
+    const XGL_UINT ve_offset = sampler_offset + rmap->sampler_count;
     struct intel_pipeline_rmap_slot *slot;
 
     switch (type) {
@@ -50,6 +51,9 @@
     case XGL_SLOT_SHADER_SAMPLER:
         slot = &rmap->slots[sampler_offset + index];
         break;
+    case XGL_SLOT_VERTEX_INPUT:
+        slot = &rmap->slots[ve_offset + index];
+        break;
     default:
         assert(!"unknown rmap slot type");
         slot = NULL;
@@ -149,6 +153,10 @@
         if (rmap->sampler_count < index + 1)
             rmap->sampler_count = index + 1;
         break;
+    case XGL_SLOT_VERTEX_INPUT:
+        if (rmap->vb_count < index + 1)
+            rmap->vb_count = index + 1;
+        break;
     default:
         assert(!"unknown rmap slot type");
         break;
@@ -225,7 +233,7 @@
     rmap->rt_count = rt_count;
 
     rmap->slot_count = rmap->rt_count + rmap->resource_count +
-        rmap->uav_count + rmap->sampler_count;
+        rmap->uav_count + rmap->sampler_count + rmap->vb_count;
 
     rmap->slots = icd_alloc(sizeof(rmap->slots[0]) * rmap->slot_count,
             0, XGL_SYSTEM_ALLOC_INTERNAL);