Avoid implicit conversion warnings in deflate.c and trees.c.

deflate.c

@@ -1671,10 +1671,10 @@ local block_state deflate_stored(deflate_state *s, int flush) {
         _tr_stored_block(s, (char *)0, 0L, last);
 
         /* Replace the lengths in the dummy stored block with len. */
-        s->pending_buf[s->pending - 4] = len;
-        s->pending_buf[s->pending - 3] = len >> 8;
-        s->pending_buf[s->pending - 2] = ~len;
-        s->pending_buf[s->pending - 1] = ~len >> 8;
+        s->pending_buf[s->pending - 4] = (Bytef)len;
+        s->pending_buf[s->pending - 3] = (Bytef)(len >> 8);
+        s->pending_buf[s->pending - 2] = (Bytef)~len;
+        s->pending_buf[s->pending - 1] = (Bytef)(~len >> 8);
 
         /* Write the stored block header bytes. */
         flush_pending(s->strm);

trees.c

@@ -724,7 +724,7 @@ local void scan_tree(deflate_state *s, ct_data *tree, int max_code) {
         if (++count < max_count && curlen == nextlen) {
             continue;
         } else if (count < min_count) {
-            s->bl_tree[curlen].Freq += count;
+            s->bl_tree[curlen].Freq += (ush)count;
         } else if (curlen != 0) {
             if (curlen != prevlen) s->bl_tree[curlen].Freq++;
             s->bl_tree[REP_3_6].Freq++;