[flashrom] AMD SB7xx/SB8xx w/IMC: enable specs

[Joshua Roys]

Hello all,

The specific board this is for is the Supermicro H8DGT.  Attached is
only the specification, which is not guaranteed to be correct.  Use with
care.

Also, after using this, you may want to turn off and unplug the computer
for a few minutes to restore the correct operational state.

The AMD SB700/710/750 Register Reference Guide (#43009) was used as a
reference.

Thanks,

Josh