Revert "block: row: Update initial values of ROW data structures"

This reverts commit 00831887f38dfe965434a7509aa18ac1fe419985.

Signed-off-by: zwliew <zhaoweiliew@gmail.com>
block: row: Dispatch requests according to their io-priority

This patch implements "application-hints" which is a way the issuing
application can notify the scheduler on the priority of its request.
This is done by setting the io-priority of the request.
This patch reuses an already existing mechanism of io-priorities developed
for CFQ. Please refer to kernel/Documentation/block/ioprio.txt for
usage example and explanations.

Change-Id: I228ec8e52161b424242bb7bb133418dc8b73925a
Signed-off-by: Tatyana Brokhman <tlinder@codeaurora.org>
Signed-off-by: zwliew <zhaoweiliew@gmail.com>

Conflicts:
	block/row-iosched.c
block/row: fix compile error for LK 3.0

Change-Id: I7e9e8b1e624e80a8ba226e863c8ee5df6d0a2638
Signed-off-by: zwliew <zhaoweiliew@gmail.com>