arm: dts: qcom: Add 8x74 chipset SPMI PMIC's nodes

PM8841 and PM8941 have 2 SPMI devices per physical package.
Add their configuration nodes and include them in boards
which are using 8x74 based chipset.

Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Kumar Gala <galak@codeaurora.org>
Signed-off-by: Olof Johansson <olof@lixom.net>