mmc: omap_hsmmc: Fix DTO and DCRC handling

DTO/DCRC errors were not being informed to the mmc core since
commit ae4bf788 ("mmc: omap_hsmmc: consolidate error report handling of
HSMMC IRQ"). This commit made sure 'end_trans' is never set on DTO/DCRC
errors. This is because after this commit 'host->data' is checked after
it has been cleared to NULL by omap_hsmmc_dma_cleanup().

Because 'end_trans' is never set, omap_hsmmc_xfer_done() is never invoked
making core layer not to be aware of DTO/DCRC errors. Because of this
any command invoked after DTO/DCRC error leads to a hang.

Fix this by checking for 'host->data' before it is actually cleared.

Fixes: ae4bf788

 ("mmc: omap_hsmmc: consolidate error report handling of
HSMMC IRQ")

CC: stable@vger.kernel.org
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Vignesh R <vigneshr@ti.com>
Tested-by: Andreas Fenkart <afenkart@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>