omap3_pandora: Only set bootargs if distro_bootcmd failed to load.

As bootargs is hard-coded for the default behavior on the
omap3_pandora, only set the bootargs if distro_bootcmd fails to
load. This leaves distro_bootcmd free to use alternate boot arguments.

Signed-off-by: Vagrant Cascadian <vagrant@debian.org>
diff --git a/include/configs/omap3_pandora.h b/include/configs/omap3_pandora.h
index fd51811..b664319 100644
--- a/include/configs/omap3_pandora.h
+++ b/include/configs/omap3_pandora.h
@@ -88,6 +88,7 @@
 
 #define CONFIG_BOOTCOMMAND \
 	"run distro_bootcmd; " \
+	"setenv bootargs ${bootargs_ubi}; " \
 	"if mmc rescan && load mmc 0:1 ${loadaddr} autoboot.scr; then " \
 		"source ${loadaddr}; " \
 	"fi; " \
@@ -102,7 +103,7 @@
 #define CONFIG_EXTRA_ENV_SETTINGS \
 	DEFAULT_LINUX_BOOT_ENV \
 	"usbtty=cdc_acm\0" \
-	"bootargs=ubi.mtd=4 ubi.mtd=3 root=ubi0:rootfs rootfstype=ubifs " \
+	"bootargs_ubi=ubi.mtd=4 ubi.mtd=3 root=ubi0:rootfs rootfstype=ubifs " \
 		"rw rootflags=bulk_read vram=6272K omapfb.vram=0:3000K\0" \
 	"mtdparts=" MTDPARTS_DEFAULT "\0" \
 	BOOTENV \