mtd: nand: qcom: add bam property for QPIC NAND controller

The current driver only supports EBI2 NAND controller which uses
ADM DMA. The latest QCOM SoC uses QPIC NAND controller with BAM
DMA. NAND registers and programming sequence are same for EBI2
and QPIC NAND so the same driver can support QPIC NAND also by
adding the BAM DMA support. This patch adds the is_bam in NAND
property which will be checked for determining the DMA engine type.

Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>