Merge pull request #545 from terrelln/force-window

[zstdmt] Fix MSAN failure with ZSTD_p_forceWindow

lib/compress/zstd_compress.c

@@ -2512,7 +2512,7 @@ static size_t ZSTD_loadDictionaryContent(ZSTD_CCtx* zc, const void* src, size_t
         return ERROR(GENERIC);   /* strategy doesn't exist; impossible */
     }
 
-    zc->nextToUpdate = zc->loadedDictEnd;
+    zc->nextToUpdate = (U32)(iend - zc->base);
     return 0;
 }