dm: core: Replace of_offset with accessor (part 2)

At present devices use a simple integer offset to record the device tree
node associated with the device. In preparation for supporting a live
device tree, which uses a node pointer instead, refactor existing code to
access this field through an inline function.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/mmc/mmc-uclass.c b/drivers/mmc/mmc-uclass.c
index 9c07871..8d03ec6 100644
--- a/drivers/mmc/mmc-uclass.c
+++ b/drivers/mmc/mmc-uclass.c
@@ -198,7 +198,7 @@
 
 #ifndef CONFIG_SPL_BUILD
 	/* Use the fixed index with aliase node's index */
-	fdtdec_get_alias_seq(gd->fdt_blob, "mmc", dev->of_offset, &devnum);
+	fdtdec_get_alias_seq(gd->fdt_blob, "mmc", dev_of_offset(dev), &devnum);
 #endif
 
 	ret = blk_create_devicef(dev, "mmc_blk", "blk", IF_TYPE_MMC,
diff --git a/drivers/mmc/sdhci-cadence.c b/drivers/mmc/sdhci-cadence.c
index 4452be0..4bd2623 100644
--- a/drivers/mmc/sdhci-cadence.c
+++ b/drivers/mmc/sdhci-cadence.c
@@ -139,7 +139,7 @@
 	host->ioaddr = plat->hrs_addr + SDHCI_CDNS_SRS_BASE;
 	host->quirks |= SDHCI_QUIRK_WAIT_SEND_CMD;
 
-	ret = sdhci_cdns_phy_init(plat, gd->fdt_blob, dev->of_offset);
+	ret = sdhci_cdns_phy_init(plat, gd->fdt_blob, dev_of_offset(dev));
 	if (ret)
 		return ret;
 
diff --git a/drivers/mmc/zynq_sdhci.c b/drivers/mmc/zynq_sdhci.c
index 70ad573..0fddb42 100644
--- a/drivers/mmc/zynq_sdhci.c
+++ b/drivers/mmc/zynq_sdhci.c
@@ -83,7 +83,7 @@
 	host->name = dev->name;
 	host->ioaddr = (void *)devfdt_get_addr(dev);
 
-	plat->f_max = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+	plat->f_max = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
 				"max-frequency", CONFIG_ZYNQ_SDHCI_MAX_FREQ);
 
 	return 0;