spi: spidev_test: Sorted the options into logical groups

In order to increase usability, the command line options are sorted into
logical groups. In addition, the usage string was sorted alphabetically,
and the missing parameters '8','i' and 'o' were added. Furthermore, the
option descriptions were moved further to the right, in order to allow
for longer option names.

Signed-off-by: Boerge Struempfel <boerge.struempfel@gmail.com>
Link: https://lore.kernel.org/r/20230530141641.1155691-5-boerge.struempfel@gmail.com


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