spi_qsd: support to transfer 64K chunks in DM mode

Support to transfer 64K bytes in a single SPI
transfer in DMA mode on targets which support
16 bits in QUP_MX_OUTPUT_CNT register. Earlier
if the application sends more than 4K data it is
split up in to 4K chunks,  irrespective of the size
of the QUP_MX_OUTPUT_CNT register.

CRs-Fixed: 383120
Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
(cherry picked from commit c5fbd7f2dccf52e95e6c1504a28b19d1dc622028)

Change-Id: Idb27c651e0a81a4efe363feabc44e26c5b61fb0f
Signed-off-by: Sudhir Sharma <sudsha@codeaurora.org>
diff --git a/drivers/spi/spi_qsd.h b/drivers/spi/spi_qsd.h
index b0d72b7..a0dee34 100644
--- a/drivers/spi/spi_qsd.h
+++ b/drivers/spi/spi_qsd.h
@@ -322,6 +322,7 @@
 	/* SPI CS GPIOs for each slave */
 	struct spi_cs_gpio       cs_gpios[ARRAY_SIZE(spi_cs_rsrcs)];
 	int                      qup_ver;
+	int			 max_trfr_len;
 };
 
 /* Forward declaration */