Add nopll command to turn off the PLL, reducing the system clock to 16Mhz.
Signed-off-by: Randall Spangler <rspangler@chromium.org>
BUG=chrome-os-partner:8798
TEST=manual
boot system
press power button to boot x86
temps // should print all temperatures
timerinfo
timerinfo
timerinfo // convince yourself this is counting up at about 1MHz
nopll // this drops the system clock to 16MHz
temps // should still print all temperatures
timerinfo
timerinfo
timerinfo // should still be counting up at about 1MHz
Change-Id: Ie29ceb17af348148bffadf63d60c1b731f4c3f6d