Third RC for flashrom-1.0

Including one workaround and updated README for DOS (DJGPP) builds.
  1. ef3ac8a Refactor unlocking of many chips with locking at register space address +2 by Carl-Daniel Hailfinger · 7 years ago
  2. beaffd8 Enable sector erase function for selected ST M50 chips by Stefan Tauner · 8 years ago
  3. 4404f73 Cleanup ST M50 driver by Stefan Tauner · 8 years ago