Stellaris: Add preliminary LPC bus mastering

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Stellaris: Hook LPC bus master to qiprog_read_id

This allows us to read the chip ID and send it back to the host.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Stellaris: Hook LPC bus master to qiprog_read/write_[8/16/32]

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Stellaris: Move LED control into separate file

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Stellaris: Repurpose red and blue LEDs to indicate LPC cycles

Turn the blue LED on during LPC read cycles, and the red LED during LPC
write cycles.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>