Davinci: ea20: added PREBOOT to configuration

PREBOOT is used on the ea20 to load a splash image
at the start up.

Signed-off-by: Stefano Babic <sbabic@denx.de>
CC: Sandeep Paulraj <s-paulraj@ti.com>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>

include/configs/ea20.h

@@ -33,6 +33,7 @@
 #define CONFIG_BOARD_EARLY_INIT_F
 #define BOARD_LATE_INIT
 #define CONFIG_VIDEO
+#define CONFIG_PREBOOT
 
 /*
  * SoC Configuration