dmaengine: stm32-dma: fix burst in case of unaligned memory address

dmaengine: stm32-dma: fix burst in case of unaligned memory address

Theorically, address pointers used by STM32 DMA must be chosen so as to
ensure that all transfers within a burst block are aligned on the address
boundary equal to the size of the transfer.
If this is always the case for peripheral addresses on STM32, it is not for
memory addresses if the user doesn't respect this alignment constraint.
To avoid a weird behavior of the DMA controller in this case (no error
triggered but data are not transferred as expected), force no burst.

Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20211011094259.315023-4-amelie.delaunay@foss.st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>