mmc: omap_hsmmc: Fix pbias_disable for omap4

pbias_disable is set to protect the mmc pbias i/o cells in DT boot
by preventing voltage switch. Currently pbias_disable is enabled only
for omap3 and not for omap4 due to reg_offset difference of 0x100.
Enable pbias_disable for omap4+ too by using res->start
which does not include the reg_offset.
Signed-off-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/host/omap_hsmmc.c

@@ -1874,7 +1874,7 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
 	omap_hsmmc_context_save(host);
 
 	/* This can be removed once we support PBIAS with DT */
-	if (host->dev->of_node && host->mapbase == 0x4809c000)
+	if (host->dev->of_node && res->start == 0x4809c000)
 		host->pbias_disable = 1;
 
 	host->dbclk = clk_get(&pdev->dev, "mmchsdb_fck");