Revert oFVM "Exercise to FVM/FTM LP" parameters to the original 40%-80%

Given the discount of 25% when exercising oFVM to directly convert to liquid FVM, it makes no sense anymore to LP 1 week and get a 30% discount. 15% more FVM after one week does not cover the risk of LPing in pool 2, and so the recent change actually incentivize insta-dumping oFVM.