Add support for the Qualcomm PM8821 PMIC chip. The core driver will communicate with the PMIC chip via the MSM SSBI bus. Initial support is provided for: IRQ, MPP, and Debug Change-Id: Ic072e634c55925292196a3e710d2dc628cbf2780 Signed-off-by: Jay Chokshi <jchokshi@codeaurora.org>