mmc: block: Fix request completion in the CQE timeout path

First, it should be noted that the CQE timeout (60 seconds) is
substantial so a CQE request that times out is really stuck, and the
race between timeout and completion is extremely unlikely. Nevertheless
this patch fixes an issue with it.

Commit ad73d6fe ("mmc: complete requests from ->timeout")
preserved the existing functionality, to complete the request.
However that had only been necessary because the block layer
timeout handler had been marking the request to prevent it from being
completed normally. That restriction was removed at the same time, the
result being that a request that has gone will have been completed
anyway.
That is, the completion was unnecessary.

At the time, the unnecessary completion was harmless because the block
layer would ignore it, although that changed in kernel v5.0.

Change-Id: I8690c293afa280bb030d114008fb00df711417f8
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: ad73d6fe ("mmc: complete requests from ->timeout")
Cc: stable@vger.kernel.org
Git-commit: c077dc5e0620508a29497dac63a2822324ece52a
Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc.git
Link: https://lore.kernel.org/r/20200508062227.23144-1-adrian.hunter@intel.com


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sarthak Garg <sartgarg@codeaurora.org>