Add a driver which allows powering off the system via an Intel PIIX4
southbridge, by entering the PIIX4 SOff state. This is useful on the
MIPS Malta development board, where it will power down the FPGA based
board until its ON/NMI button is pressed, or the QEMU implementation of
the MIPS Malta board where it will cause QEMU to exit.
Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-pm@vger.kernel.org
Signed-off-by: NSebastian Reichel <sre@kernel.org>