omap3: igep0x00: Update for DM SPL support

This change is heavily based on commit e0cc7df9fdf2 ("omap3_beagle: Update
for DM SPL support"), that did the same update for the OMAP3 Beagle board.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Enric Balletbo i Serra <eballetbo@gmail.com>
diff --git a/arch/arm/dts/omap3-igep0020-u-boot.dtsi b/arch/arm/dts/omap3-igep0020-u-boot.dtsi
index 41beaf0..2c03701 100644
--- a/arch/arm/dts/omap3-igep0020-u-boot.dtsi
+++ b/arch/arm/dts/omap3-igep0020-u-boot.dtsi
@@ -5,20 +5,10 @@
  * (C) Copyright 2017 Derald D. Woods <woods.technical@gmail.com>
  */
 
+#include "omap3-u-boot.dtsi"
+
 / {
 	chosen {
 		stdout-path = &uart3;
 	};
 };
-
-&uart1 {
-	reg-shift = <2>;
-};
-
-&uart2 {
-	reg-shift = <2>;
-};
-
-&uart3 {
-	reg-shift = <2>;
-};