* LFP chief denies involvement in doping at Real Sociedad * Allegations made by former Sociedad president Badiola * Club says has a "zero tolerance" policy towards doping (Adds Sociedad statement) MADRID, Feb 4 (Reuters) - The head of Spain's professional soccer league (LFP), Jose Luis Astiazaran, has denied allegations made in As sports daily on Monday that he was complicit in the provision of banned substances to players while president of Real Sociedad. ... More...