linux-wandboard

mmc: sdhci-pxav3: Document clocks and additional clock-names property

Now that sdhci-pxav3 driver allows to have more than one IP clock defined,
document both clocks and clock-names properties.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>