spi/imx: select master mode for all channels
spi/imx: select master mode for all channels

The hardware seems to have a race condition when the inactive
channels are in slave mode. We support master mode only, so
we can just switch all channels to master mode.

Signed-off-by: Sascha Hauer <c00cbc2b736c26791a3822db86f8796fe9efff67@pengutronix.de>
[ukleinek: add more verbose comment about the race]
Signed-off-by: Uwe Kleine-König <181323dd666a182bc2d953e52d0ac3ab54cd8391@pengutronix.de>
Signed-off-by: Grant Likely <9069e6f5a2b566e2674a0ba1e2bf39c12c195fad@secretlab.ca>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas