spi: pxa2xx: use min() instead of min_t()

spi: pxa2xx: use min() instead of min_t()

min_t(int, a, b) casts an 'u32' to 'int'. This might lead to
the cases when big number is wrongly chosen. On the other hand,
the SPI transfer speed rate is unsigned and driver uses signed type
for an unknown reason. Change the type of the SPI transfer speed
to be unsigned and convert to use min() instead of min_t().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: David Laight <david.laight.linux@gmail.com>
Link: https://patch.msgid.link/20260223153117.2838840-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>