arm64: dts: imx8mq-evk: add one regulator used to power up pcie phy

Both 1.8v and 3.3v power supplies can be used by i.MX8MQ PCIe PHY.
In default, the PCIE_VPH voltage is suggested to be 1.8v refer to data
sheet. When PCIE_VPH is supplied by 3.3v in the HW schematic design,
the VREG_BYPASS bits of GPR registers should be cleared from default
value 1b'1 to 1b'0. Thus, the internal 3v3 to 1v8 translator would be
turned on.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mq-evk.dts

@@ -318,6 +318,7 @@ &pcie0 {
 		 <&clk IMX8MQ_CLK_PCIE1_PHY>,
 		 <&pcie0_refclk>;
 	clock-names = "pcie", "pcie_aux", "pcie_phy", "pcie_bus";
+	vph-supply = <&vgen5_reg>;
 	status = "okay";
 };