Clean all defconfigs with savedefconfig

In order to reduce merge conflicts and to maintain the simplest possible
defconfig files, we should be using the savedefconfig feature of Kconfig
every time a new feature is added. This keeps the defconfig settings to
a minimum (only those things not default) and keeps them in the same
order as the Kconfig options.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Cc: Tom Rini <trini@konsulko.com>