refine code, add install root message

@@ -111,5 +111,6 @@ echo ""
 echo "see: https://github.com/winlinvip/simple-rtmp-server/wiki/LinuxService"
 echo "install success, you can:"
 echo -e "${GREEN}      sudo /etc/init.d/srs start${BLACK}"
+echo "srs root is ${INSTALL}"
 
 exit 0

@@ -216,8 +216,6 @@ namespace _srs_internal
     {
         int ret = ERROR_SUCCESS;
         
-        int32_t bits_count = 1024; 
-        
         // create DH and copy the 128bytes public key
         if ((ret = __openssl_copy_key(pdh, public_key, ppk_size)) != ERROR_SUCCESS) {
             return ret;