etherbone: add etherbone slave (= wishbone master)
memtest: shrink memtest space to 63M for lx9 microboard
lx9crg: add crg for lx9 microboard
software/bios: temporarily disable crcbios()

fails if flash is not working
top.py, lm32_config.v, linker.ld: use static hardcoded rom for bios
remaining changes for lx9 microboard