If we have Linux installed in eMMC we can boot without
µSD card, but inserting one is not recognised.
The reason is that the card detect gpio (gpio5_152)
is not configured and attached to the mmc1 interface
driver and the mmc driver does not poll by default.
Hence we add pinmux and gpio setup for the SDCARD_NCD
signal.
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com> Signed-off-by: Tony Lindgren <tony@atomide.com>