SOQUARTZ: drive nEXTRST high on boot (#63)

This is used by carriers boards to get some devices
(e.g. USB hub) out of reset.

edk2-rockchip/Platform/Pine64/SOQuartz/Drivers/BoardInitDxe/BoardInitDxe.c

@@ -57,7 +57,7 @@
 
 /*
  * PMIC registers
-*/
+ */
 #define PMIC_I2C_ADDR           0x20
 
 #define PMIC_CHIP_NAME          0xed
@@ -309,5 +309,13 @@ BoardInitDriverEntryPoint (
   /* WiFi setup */
   BoardInitWiFi ();
 
+  /*
+   * Set GPIO0 PA5 (nEXTRST) output high,
+   * "Driven high (CM4_3.3V) once CM4 CPU has started to boot".
+   * Used to get external devices out of reset state.
+   */
+  GpioPinSetDirection (0, GPIO_PIN_PA5, GPIO_PIN_OUTPUT);
+  GpioPinWrite (0, GPIO_PIN_PA5, TRUE);
+
   return EFI_SUCCESS;
 }