国产系统sane_read流程是否结束，通过读取size大小判断改为返回一次SANE_STATUS_EOF判断

modules/sane_user/HGSaneImpl.cpp

@@ -1059,7 +1059,7 @@ void HGAPI HGSaneDeviceImpl::ThreadFunc(HGThread thread, HGPointer param)
 
         SANE_Int readSize = 0;
         SANE_Status stat2 = SANE_STATUS_GOOD;
-        while (readSize < bufferSize)
+        while (SANE_STATUS_EOF != stat2)
         {
             SANE_Int len = 0;
             stat2 = saneAPI.sane_read_api(p->m_devHandle, buffer + readSize, bufferSize - readSize, &len);