dmaengine: DW DMAC: add multi-block property to device tree

Several versions of DW DMAC have multi block transfers hardware
support. Hardware support of multi block transfers is disabled
by default if we use DT to configure DMAC and software emulation
of multi block transfers used instead.
Add multi-block property, so it is possible to enable hardware
multi block transfers (if present) via DT.

Switch from per device is_nollp variable to multi_block array
to be able enable/disable multi block transfers separately per
channel.

Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/tty/serial/8250/8250_lpss.c

@@ -157,12 +157,12 @@ static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port)
 static const struct dw_dma_platform_data qrk_serial_dma_pdata = {
 	.nr_channels = 2,
 	.is_private = true,
-	.is_nollp = true,
 	.chan_allocation_order = CHAN_ALLOCATION_ASCENDING,
 	.chan_priority = CHAN_PRIORITY_ASCENDING,
 	.block_size = 4095,
 	.nr_masters = 1,
 	.data_width = {4},
+	.multi_block = {0},
 };
 
 static void qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port)