ARM: u300: u300_defconfig: Enable PARTITION_ADVANCED

Since there are SD-card support in u300, it's reasonable to
support partitions for block devices as default.

While updating the defconfig, we rebase it towards Kconfig changes.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>