spi/atmel: Fix format specifier warnings

spi/atmel: Fix format specifier warnings

This patch fixes the following sparse warnings.
dma_addr_t can be either u32 or u64 so we should cast to the
largest type and use the format specifier %llx.

drivers/spi/spi-atmel.c: In function ‘atmel_spi_next_xfer_dma_submit’:
drivers/spi/spi-atmel.c:631:2: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 7 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c:631:2: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 9 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c: In function ‘atmel_spi_pdc_next_xfer’:
drivers/spi/spi-atmel.c:734:3: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 7 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c:734:3: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 9 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c:773:3: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 7 has type ‘dma_addr_t’ [-Wformat]
drivers/spi/spi-atmel.c:773:3: warning:
	format ‘%x’ expects argument of type ‘unsigned int’,
	but argument 9 has type ‘dma_addr_t’ [-Wformat]

Signed-off-by: Emil Goode <emilgoode@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>