Core: make ngx_connection_local_sockaddr() always assign address.
Core: make ngx_connection_local_sockaddr() always assign address.

Previously, this function checked for connection local address existence
and returned error if it was missing.  Now a new address is assigned in this
case making it possible to call this function not only for accepted connections.

hy0kl/nginx,hy0kl/nginx,hy0kl/nginx