TOKYO – Nuclear power returned to Japan’s energy mix for the first time in two months Thursday, hours before a parliamentary panel blamed the government’s cozy relations with the industry for the meltdowns that prompted the mass shutdown of the nation’s reactors. Though the report echoes other investigations into last year’s disaster at the Fukushima Dai-ichi plant, it could fuel complaints that Japan is trying to restart nuclear reactors without doing enough to avoid a repeat. Thursday’s resumption of operations at a reactor in Ohi, in western Japan, already had been hotly contested.