use SDL_zeroa at more places where the argument is an array.

src/main/haiku/SDL_BApp.h

@@ -285,7 +285,7 @@ private:
             ssize_t count;
             if (msg->FindData("key-utf8", B_INT8_TYPE, (const void**)&keyUtf8, &count) == B_OK) {
                 char text[SDL_TEXTINPUTEVENT_TEXT_SIZE];
-                SDL_zero(text);
+                SDL_zeroa(text);
                 SDL_memcpy(text, keyUtf8, count);
                 SDL_SendKeyboardText(text);
             }