sdhci-bcm2807: Increase sync_after_dma timeout

The current timeout is being hit with some cards that complete successfully with a longer timeout.
The timeout is not handled well, and is believed to be a code path that causes corruption.
872a8ff suggests that crappy cards can take up to 3 seconds to respond

drivers/mmc/host/sdhci-bcm2708.c

@@ -842,7 +842,7 @@ static void sdhci_bcm2708_dma_complete_irq(struct sdhci_host *host,
 			   We get CRC and DEND errors unless we wait for
 			   the SD controller to finish reading/writing to the card. */
 			u32 state_mask;
-			int timeout=30*5000;
+			int timeout=3*1000*1000;
 
 			DBG("PDMA over - sync card\n");
 			if (data->flags & MMC_DATA_READ)