[ARM] pxa: merge {zylonite,littleton}_defconfig into pxa3xx_defconfig

Merge zylonite_defconfig and littleton_defconfig into pxa3xx_defconfig.
Since they're similar platform and servicing for same SoC family.

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
3 files changed