serprog: add opcode to control the programmer's output drivers

This allowed me to let the clips remain attached on my D946GZIS while
playing with coreboot/serialice.

Corresponding to flashrom svn r1618.

Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
3 files changed