[U-Boot] [PATCH v3] omap3_beagle: enable the use of a plain text file named uEnv.txt instead of boot.scr

[Paulraj, Sandeep]

> From: Alexander Holler <holler at ahsoftware.de>
> 
> Using the new env import command it is possible to use plain text files
> instead
> of script-images. Plain text files are much easier to handle.
> 
> E.g. If your boot.scr contains the following:
> -----------------------------------
> setenv dvimode 1024x768-16 at 60
> run loaduimage
> run mmcboot
> -----------------------------------
> you could create a file named uEnv.txt and use that instead of boot.scr:
> -----------------------------------
> dvimode=1024x768-16 at 60
> uenvcmd=run loaduimage; run mmcboot
> -----------------------------------
> The variable uenvcmd (if existent) will be executed (using run) after
> uEnv.txt
> was loaded. If uenvcmd doesn't exist the default boot sequence will be
> started,
> therefore you could just use
> -----------------------------------
> dvimode=1024x768-16 at 60
> -----------------------------------
> as uEnv.txt because loaduimage and mmcboot is part of the default boot
> sequence.
> 
> For backwards compatibility the use of boot.scr is still supported.
> ---
> Changes for v2:
>   - Eliminated else redundant clause that would be ignored if boot
>     succeeds.
> 
> Changes for v3:
>   - Removed boot.scr per discussion with Alexander.
> 
> Signed-off-by: Jason Kridner <jkridner at beagleboard.org>
> ---

Pushed to u-boot-ti after making changes to the patch header