ARM: dts: omap3-gta04a4: fix model name for A4 variant

GTA04 is the project name and Letux 2804 the product name.
Report both.
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/omap3-gta04a4.dts

@@ -9,5 +9,5 @@
 #include "omap3-gta04.dtsi"
 
 / {
-	model = "Goldelico GTA04A4";
+	model = "Goldelico GTA04A4/Letux 2804";
 };