ARM: tegra: colibri_t20: iris: simplify model and compatible properties

Simplify model and compatible by dropping the 256/512 MB from the model,
-512 from the compatible and rename that property from toradex,iris to
toradex,colibri_t20-iris to be more in-line with all our other device
trees.

Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

arch/arm/boot/dts/tegra20-colibri-iris.dts

@@ -6,7 +6,8 @@
 
 / {
 	model = "Toradex Colibri T20 on Iris";
-	compatible = "toradex,iris", "toradex,colibri_t20", "nvidia,tegra20";
+	compatible = "toradex,colibri_t20-iris", "toradex,colibri_t20",
+		     "nvidia,tegra20";
 
 	aliases {
 		rtc0 = "/i2c@7000c000/rtc@68";