mmc: omap_hsmmc: fix request done for sbc error case

mrq is not populated for set block count(cmd23) command.
Use block read/write mmc_commond pointer for request done and
avoid NULL pointer access in error case for sbc (cmd23).

Signed-off-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Chris Ball <chris@printf.net>
diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 6cb4e19..40914f5 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -916,7 +916,7 @@
 		}
 	}
 	if ((host->data == NULL && !host->response_busy) || cmd->error)
-		omap_hsmmc_request_done(host, cmd->mrq);
+		omap_hsmmc_request_done(host, host->mrq);
 }
 
 /*