Fix clang warnings.

* src/cffload.c (cff_blend_doBlend): Fix type of `sum`.
* src/truetype/ttgxvar.c (tt_var_load_item_variation_store): Fix type of
  `word_delta_count`.

src/cff/cffload.c

@@ -1361,7 +1361,7 @@
     for ( i = 0; i < numBlends; i++ )
     {
       const FT_Int32*  weight = &blend->BV[1];
-      FT_UInt32        sum;
+      FT_Fixed         sum;
 
 
       /* convert inputs to 16.16 fixed point */

src/truetype/ttgxvar.c

@@ -621,10 +621,10 @@
     {
       GX_ItemVarData  varData = &itemStore->varData[i];
 
-      FT_UInt  item_count;
-      FT_UInt  word_delta_count;
-      FT_UInt  region_idx_count;
-      FT_UInt  per_region_size;
+      FT_UInt    item_count;
+      FT_UShort  word_delta_count;
+      FT_UInt    region_idx_count;
+      FT_UInt    per_region_size;
 
 
       if ( FT_STREAM_SEEK( offset + dataOffsetArray[i] ) )