omap_hsmmc: Do not expect cmd/data to be non-null when CC/TC occurs

With spurious interrupt cmd can be null even when we have CC
set in irq status.

Fixes: NB#106295 - prevent potential kernel crash in the MMC driver
Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>

drivers/mmc/host/omap_hsmmc.c

@@ -493,7 +493,7 @@ static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
 	/* Flush posted write */
 	OMAP_HSMMC_READ(host->base, STAT);
 
-	if (end_cmd || (status & CC))
+	if (end_cmd || ((status & CC) && host->cmd))
 		mmc_omap_cmd_done(host, host->cmd);
 	if (end_trans || (status & TC))
 		mmc_omap_xfer_done(host, data);