dev: Set the "status" field of the HDLCD device tree node to "ok".

This makes the kernel enable the device.

Change-Id: I2c237b9ba038c5128e2a7e020587ac46ef7b4abd
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/37936
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/dev/arm/RealView.py

@@ -531,7 +531,7 @@ class HDLcd(AmbaDmaDevice):
     pixel_chunk = Param.Unsigned(32, "Number of pixels to handle in one batch")
     virt_refresh_rate = Param.Frequency("20Hz", "Frame refresh rate "
                                         "in KVM mode")
-    _status = "disabled"
+    _status = "ok"
 
     encoder = Param.Display(Display1080p(), "Display encoder")
 
@@ -563,10 +563,6 @@ class HDLcd(AmbaDmaDevice):
         node.append(FdtPropertyWords("clocks", state.phandle(self.pxl_clk)))
         node.append(FdtPropertyStrings("clock-names", ["pxlclk"]))
 
-        # This driver is disabled by default since the required DT nodes
-        # haven't been standardized yet. To use it,  override this status to
-        # "ok" and add the display configuration nodes required by the driver.
-        # See the driver for more information.
         node.append(FdtPropertyStrings("status", [ self._status ]))
 
         self.addIommuProperty(state, node)