mtd: parsers: Add Qcom SMEM parser

NAND based Qualcomm platforms have the partition table populated in the
Shared Memory (SMEM). Hence, add a parser for parsing the partitions
from it.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210104041137.113075-3-manivannan.sadhasivam@linaro.org