sfc: Clean up non-volatile memory partitioning

Move flash and EEPROM partition boundary constants into spi.h and rename
them to be consistent.

Add a comment on the partitioning.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
4 files changed