Since the Data Strobe pin is optional, take it out of the default
eMMC pins and add a separate entry.
Signed-off-by: NNeil Armstrong <narmstrong@baylibre.com>
Tested-by: NJerome Brunet <jbrunet@baylibre.com>
Signed-off-by: NKevin Hilman <khilman@baylibre.com>