defconfig: sdm855: Enable NVMEM_SPMI_SDAM support

Shared Direct Access Memory (SDAM) is used by some PMIC
peripheral drivers to store and pass information. Add
support for it.

Change-Id: I417896f0cf1435ed5369280beaa8467df57c942d
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>