defconfig: branding

As well as make it proper so it gives good and working builds
Change-Id: I008962c164a408295d9a0df7090590010b1b9779

Conflicts:
	arch/arm/configs/hammerhead_defconfig
defconfig: Revert to GZIP compression

XZ offers no advantages. With proper dtb inline build, zImages size is
now absolutely normal.

Change-Id: I88fefcdb413fc9b5922e5a515a928fa3bee18ae9
defconfig: Add CONFIG_NETFILTER_XT_TARGET_TCPMSS support

Bug: 11579326

Commit adb2201560 AOSP upstream.

Signed-off-by: Patrick Tjin <pattjin@google.com>

Change-Id: I048d3b5ee1f8a73f002aa9850a4c1bbbef535738