arm: am335x-pdu001: Enable CONFIG_BLK and CONFIG_DM_MMC
This patch enables CONFIG_BLK as well as CONFIG_DM_MMC for the PDU001
board. It depends on Patrice Chotard's patch 'power: regulator: denied
disable on always-on regulator' which prevents power cycling the vmmc
supply. Without this patch the board will not boot as vmmc is
unfortunately used by other board components, not just eMMC and micro SD
card. Furthermore my patch 'dts: am335x-pdu001: Fix polarity of card
detection input' is required to boot from external micro SD card. Without
this patch no SD card will be detected and hence booting will fail.
Signed-off-by: Felix Brack <fb@ltec.ch> Reviewed-by: Tom Rini <trini@konsulko.com>