By Christoph Steitz FRANKFURT (Reuters) – Siemens Energy has stepped up efforts to explore a full integration of wind turbine business Siemens Gamesa, sources told Reuters, after profit warnings and share price slumps last week exposed flaws in the current ownership structure. The company is currently working with advisers to look at options for how to best acquire the remaining 33% stake Siemens Energy does not yet own in Siemens Gamesa, two people familiar with the matter said. Siemens Energy CEO Christian Bruch is under pressure to find a way to sort out the ownership structure inherited as…