defconfig: sdmsteppeauto: Enable SPMI PMIC drivers

Enable MFD SPMI PMIC driver and several SPMI and PMIC drivers
which are needed to provide baseline support of PMIC peripherals.

Change-Id: I965b40eb0931c2e22e9fab28626e9ca753ad3ff8
Signed-off-by: Veera Vegivada <vvegivad@codeaurora.org>