media: sun6i: fix spelling mistake "droped" -> "dropped"

There are spelling mistakes in dev_dbg messages, fix them.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>