spi: spi-fsl-dspi: Bug fix incorrect CS de-assert
spi: spi-fsl-dspi: Bug fix incorrect CS de-assert

SPI chip select signal need to keep asserted between several
spi_transfer in the same spi_message usually.
But the driver will de-assert CS signal and the assert it between
serval spi_transfer in the same spi_message under some condiations.
This patch fix the bug.

Here is an example:
Assume you have two variables like the following,
struct spi_transfer a;
struct spi_transfer b;
if you send a spi_message only includes 'a' first,
and then you send a spi_message includes 'a' and 'b'
but without resetting 'a'.
Driver will de-assert CS and then assert CS between 'a' and 'b'.

Signed-off-by: Haikun Wang <b54d275ad23e9762c1c66d744b66653f259d585d@freescale.com>
Signed-off-by: Mark Brown <b51b9a92386687a9ac927cebfa0f978adeb8cea5@kernel.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs