spi: bcm2835aux: use 'unsigned int' instead of 'unsigned'

Prefer 'unsigned int' to bare use of 'unsigned'.

Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Link: https://lore.kernel.org/r/20210731133342.432575-1-wangborong@cdjrlc.com


Signed-off-by: Mark Brown <broonie@kernel.org>