Install out of tree configs for Chrome OS builds of U-Boot.

Install out of tree configs for Chrome OS builds of U-Boot.

BUG=None
TEST=emerge-tegra2_seaboard -av u-boot-config; verify that seaboard configs are installed.
emerge-tegra2_seaboard -auDN --selective=n chromeos-u-boot-next; verify that the build is not effected by the extra environment variable.  And that the resulting U-Boot boots Chromium OS on Seaboard.

Change-Id: Iedee3fd8400892152206f992b91640b5897f6ca2

This CL depends on: http://codereview.chromium.org/6759035/
                    https://chromereviews.googleplex.com/2704015/

Committed: http://chrome-svn/viewvc/chromeos?view=rev&revision=3996841

[sjg, 2011-03-30 23:30:58]

How does the u-boot-config ebuild get unmasked? For me it complains about the
~arm.

Also do you have a CL that adds the src/platform/u-boot-config files?

[robotboy, 2011-03-30 23:33:33]

On 2011/03/30 23:30:58, sjg wrote:
> How does the u-boot-config ebuild get unmasked? For me it complains about the
> ~arm.
> 
> Also do you have a CL that adds the src/platform/u-boot-config files?

Since the u-boot-config ebuild is a 9999 ebuild it comes masked.  You either
have to manually unmask it or cros_workon start it to test this change.  The
src/platform/u-boot-config repository should not be populated.  Just repo sync
and you should see it.

Thanks,
    Anton

[sjg, 2011-03-30 23:50:29]

Sorry I missed this. LGTM

[Che-Liang Chiou, 2011-03-31 03:51:39]

LGTM.