spi: sun4i: fix typos in comments

Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20220314115354.144023-22-Julia.Lawall@inria.fr


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