scsi: ufs-qcom: Name the dev_ref_clk_ctrl registers

In preparation for adding another optional register range to the ufs-qcom
driver, name the existing optional register range "dev_ref_clk_ctrl_mem".
This allows the driver to refer to the optional register ranges by name
rather than index.

No device-tree files actually have to be updated due to this change, since
none of them actually declares these registers.

Link: https://lore.kernel.org/r/20200710072013.177481-3-ebiggers@kernel.orgReviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ufs/ufs-qcom.c

@@ -1275,7 +1275,8 @@ static int ufs_qcom_init(struct ufs_hba *hba)
 		host->dev_ref_clk_en_mask = BIT(26);
 	} else {
 		/* "dev_ref_clk_ctrl_mem" is optional resource */
-		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+		res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+						   "dev_ref_clk_ctrl_mem");
 		if (res) {
 			host->dev_ref_clk_ctrl_mmio =
 					devm_ioremap_resource(dev, res);