Translate .../scsi/scsi_mid_low_api.rst into Chinese.
Add scsi_mid_low_api into .../scsi/index.rst.
Update the translation through commit 73349697fd
("scsi: docs: Clean up some style in scsi_mid_low_api")
Signed-off-by: doubled <doubled@leap-io-kernel.com>
Signed-off-by: Alex Shi <alexs@kernel.org>
