SPI: Freescale iMX SPI controller driver fixes

Fix 2 bugs:

- SPI_DMA_RHDMA bad value.

- Missing return value in setup() function (lost passing from
  patch-2.6.20-rc4-spi_imx to patch-2.6.20-rc6-spi_imx).

Signed-off-by: Andrea Paterniani <a.paterniani@swapp-eng.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>