mmc: queue: Remove unused parameters(request_queue)

In function mmc_exit_request, the request_queue structure(*q) is not used.
I remove the unnecessary code related to the request_queue structure.

Signed-off-by: ChanWoo Lee <cw9316.lee@samsung.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20210825074601.8881-1-cw9316.lee@samsung.com


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>