spi: spi-davinci: Fix variable type

'prescale' contains the return value of davinci_spi_get_prescale()
which is a signed integer. Convert 'prescale' to integer to silence
the following warning:
drivers/spi/spi-davinci.c:318 davinci_spi_setup_transfer() warn:
unsigned 'prescale' is never less than zero.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c
index 8fbfe2483ffd..8a04f1e05db2 100644
--- a/drivers/spi/spi-davinci.c
+++ b/drivers/spi/spi-davinci.c
@@ -279,7 +279,8 @@ static int davinci_spi_setup_transfer(struct spi_device *spi,
         struct davinci_spi *dspi;
         struct davinci_spi_config *spicfg;
         u8 bits_per_word = 0;
-        u32 hz = 0, spifmt = 0, prescale = 0;
+        u32 hz = 0, spifmt = 0;
+        int prescale;
 
         dspi = spi_master_get_devdata(spi->master);
         spicfg = (struct davinci_spi_config *)spi->controller_data;