block, bfq: cleanup the repeated declaration

Function 'bfq_entity_to_bfqq' is declared twice, so remove the
repeated declaration and blank line.

Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Link: https://lore.kernel.org/r/1629872391-46399-1-git-send-email-zhangshaokun@hisilicon.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>