Rename Numonyx and ST (SGS/Thomson) chips to Micron.

Micron acquired Numonyx and asked us to change the vendor names to
"Micron". For the chips clearly emerging from the former
manufacturers we (will) use "Micron/Numonyx/ST" and the original
name for the rest. Resorting the chip entries makes the diff
unreadable, hence the stand-alone commit.