block: Update ROW I/O scheduler

Signed-off-by: zwliew <zhaoweiliew@gmail.com>
block: row: add magic values.

Change-Id: Id9da9b152b9ff4fb0f35898d786c4c515cef6a5e
Signed-off-by: franciscofranco <franciscofranco.1990@gmail.com>
Signed-off-by: zwliew <zhaoweiliew@gmail.com>