Enable /proc/config.gz, save the results during LAVA testing and publish on android-build

Headline:
Runtime kernel config is now available from android-build.

Acceptance:
The kernel config is captured during LAVA testing and a pointer to it is listed on android-build.

[fgiff, 20111117]
Need a change in Jenkins config to store build artifact. Everything else is done now.

[fgiff, 20111107]
Confirmed that vexpress already generates config.gz

[fgiff, 20111103]
Only Snowball needed a kernel config update. I've updated the landing kernel and just need to do the staging kernel.

[fgiff, 20111031]
Looks like there are two items here:
 1. Preserve the kernel .config file as a build artifact stored on a-b.l.o.
 2. Preserve the kernel .config file within the kernel itself (i.e. enable generation of config.gz).

(1) is something we can implement in the a-b.l.o build scripts. (2) is something we can implement by changing all the kernel configs (IKCONFIG=y, IKCONFIG_PROC=y). Neither of these need to involve LAVA.

Work items:
Preserve the kernel .config file as a build artifact stored on a-b.l.o: DONE
Preserve the kernel .config file within the kernel itself (i.e. enable generation of config.gz): DONE
Update defconfig for tracking-panda: DONE
Update defconfig for staging-snowball: DONE
Update defconfig for staging-panda: DONE
Update defconfig for staging-imx53: DONE
Update defconfig for panda: DONE
Update defconfig for landing-snowball: DONE
Update defconfig for beagle: DONE
Update defconfig for origen: DONE