By Joanna Plucinska, Abhijith Ganapavaram and Tim Hepher LONDON (Reuters) -Boeing shares listed in Frankfurt and in U.S. pre-market trading fell almost 8% early on Monday after the U.S. Federal Aviation Administration ordered the temporary grounding of some Boeing 737 MAX 9 jets. A piece of fuselage tore off an Alaska Airlines jet on Friday following takeoff from Portland, Oregon, forcing pilots to turn back. Boeing competes with Airbus, which has expanded its market share since two Boeing MAX crashes in 2018 and 2019 that killed nearly 350 people and led to the MAX’s worldwide grounding for 2…