This prevents it from being of type PROGBITS in lld 9, it should always
be NOBITS. It should fix the following error in lld 9:
ROM segments are non-contiguous
LLD version 8 has added support for armv6m:
https://reviews.llvm.org/D55555
This means we can use LLD instead of arm-none-eabi-ld, eliminating our
dependency on GNU binutils.
There are small differences in code size, but never more than a few
bytes.