Left-hander Travis Wood and right-hander Carlos Villanueva don’t like what they’re hearing, so they plan to do something about it. The two guys left out of the Cubs’ starting-rotation plans outlined Thursday by manager Dale Sveum said Friday they plan to try to change his mind. ‘‘There’s always time to change somebody’s mind,’’ said Villanueva, who chose the Cubs as a free agent this winter because of his relationships with Sveum and pitching coach Chris Bosio — and a chance to start. ‘‘Nothing’s set in stone.’’ Since last month, the Cubs have said right-handers Jeff Samardzija, Matt Garza and Edwin Jackson are locks for the rotation. Right-hander Scott Baker will join the rotation when his post-Tommy John surgery work is done — probably a week or two into the regular season. That left right-hander Scott Feldman, Wood and Villanueva competing for two spots in the opening five — one spot once Baker returns.