phy: rockchip: emmc, add vendor prefix to dts properties

Update the implementation add "rockchip," vendor prefix for the
optional dts properties. Prefix referred from vendor-prefixes.yaml.
Follow up with
commit 8b5c2b45b8f0a ("phy: rockchip: set pulldown for strobe line in dts")
commit a8cef928276bb ("phy: rockchip-emmc: output tap delay dt property")

Signed-off-by: Chris Ruehl <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

drivers/phy/rockchip/phy-rockchip-emmc.c

···
 	if (!of_property_read_u32(dev->of_node, "drive-impedance-ohm", &val))
 		rk_phy->drive_impedance = convert_drive_impedance_ohm(pdev, val);
 
-	if (of_property_read_bool(dev->of_node, "enable-strobe-pulldown"))
+	if (of_property_read_bool(dev->of_node, "rockchip,enable-strobe-pulldown"))
 		rk_phy->enable_strobe_pulldown = PHYCTRL_REN_STRB_ENABLE;
 
-	if (!of_property_read_u32(dev->of_node, "output-tapdelay-select", &val)) {
+	if (!of_property_read_u32(dev->of_node, "rockchip,output-tapdelay-select", &val)) {
 		if (val <= PHYCTRL_OTAPDLYSEL_MAXVALUE)
 			rk_phy->output_tapdelay_select = val;
 		else