monitor: include previous targets and tachs in PEL

To discover the source of certain fan ramp-up failures, this change
outputs the previous 8 targets and tach readings. The strategy is to see
if hardware limitations prevent attaining the targets quickly enough.

Signed-off-by: Mike Capps <mikepcapps@gmail.com>
Change-Id: Ia38867986b8a8a651de5d01766393c07d413273c
4 files changed