I notice kernel.org is down, but I didn’t notice that android source code was hosted on kernel.org too. So to fix the issue is to link to an alternative new android mirror.
$repo init -you git://codeaurora.org/platform/manifest.git $repo sync
You can check out the gitweb through here.
Alternatively, another link is from CyanogenMod
$repo init -u git://github.com/CyanogenMod/android.git -b gingerbread $repo sync
Check here for using Linaro.org. http://www.linaro.org/linaro-blog/2011/09/15/%EF%BB%BFbuilding-a-linaro-android-build-from-source/