Removed unused grid_t member extraData.

src/cdf_lazy_grid.c

@@ -26,7 +26,6 @@ static bool cdfLazyInitialized;
 
 void cdfLazyGridDestroy(struct cdfLazyGrid *lazyGrid)
 {
-  lazyGrid->base.extraData = NULL;
   if (lazyGrid->base.area == cdfPendingLoad)  lazyGrid->base.area = NULL;
   if (lazyGrid->base.x.vals == cdfPendingLoad) lazyGrid->base.x.vals = NULL;
   if (lazyGrid->base.y.vals == cdfPendingLoad) lazyGrid->base.y.vals = NULL;

src/grid.c

@@ -170,7 +170,6 @@ void grid_init(grid_t *gridptr)
   memset(gridptr->uuid, 0, CDI_UUID_SIZE);
   gridptr->name          = NULL;
   gridptr->vtable        = &cdiGridVtable;
-  gridptr->extraData     = NULL;
   gridptr->atts.nalloc   = 0;
   gridptr->atts.nelems   = 0;
 }

src/grid.h

@@ -130,7 +130,6 @@ struct grid_t {
   struct gridaxis_t x;
   struct gridaxis_t y;
   const struct gridVirtTable *vtable;
-  void   *extraData;
   cdi_atts_t atts;
 };