ASoC: fsl: imx-pcm-fiq: use correct format specifier

Documentation/printk-formats.txt has
size_t: use %zu or %zx

runtime->dma_bytes is of type size_t.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>