block: open code __blk_account_io_start()

[ Upstream commit e165fb4d ]

There is only one caller for __blk_account_io_start(), the function
is small enough to fit in its caller blk_account_io_start().

Remove the function and opencode in the its caller
blk_account_io_start().

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20230327073427.4403-2-kch@nvidia.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: 99dc4223 ("block: support to account io_ticks precisely")
Signed-off-by: Sasha Levin <sashal@kernel.org>