spi: enable sending multiple SPI messages

DMA will freeze when transfering 8 bytes/8 bits,
16 bytes/16 bits, 32 bytes/32 bits. Disable it
for temporary. Meanwhile, enable the functions
to transfer multiple SPI messages by one time.

Cherry-pick from:
https://github.com/01org/edison-linux/commit/c527c66918be70f90255bf85d6435c2615bbd6bb

Signed-off-by: Shimin Zhou <shimingx.zhou@intel.com>
Signed-off-by: Chunguang Chen <chunguangx.chen@intel.com>
BUG=26065307
Change-Id: I14f5c10c9d5183553e608ceb9c40307f79d6b625
2 files changed