miner: always update block template when starting

This fixes using the previous address when starting mining,
then stopping and restarting with a different address

src/cryptonote_basic/miner.cpp

@@ -289,7 +289,6 @@ namespace cryptonote
       return false;
     }
 
-    if(!m_template_no)
     request_block_template();//lets update block template
 
     boost::interprocess::ipcdetail::atomic_write32(&m_stop, 0);