Gallium adjusts the vertrix attrib types for doubles, but can run out of
bounds this way. As the slot is counted from 0 anyway, just fix it.
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Tested-by: Ben Skeggs <bskeggs@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5512>
             info->numPatchConstants = MAX2(info->numPatchConstants, index + slots);
          break;
       case Program::TYPE_VERTEX:
+         if (slot >= VERT_ATTRIB_GENERIC0)
+            slot = VERT_ATTRIB_GENERIC0 + vary;
          vert_attrib_to_tgsi_semantic((gl_vert_attrib)slot, &name, &index);
          switch (name) {
          case TGSI_SEMANTIC_EDGEFLAG: