Add support for the Qualcomm PM8018 PMIC chip. The core driver will communicate with the PMIC chip via the MSM SSBI bus. Initial support is provided for: IRQ, GPIO, MPP, RTC, Power Key, Misc, and Debug Change-Id: I5787768603cb34bd3c9486d5c7d3fcf27a781ee9 Signed-off-by: David Collins <collinsd@codeaurora.org>