mmc: sdhci: add quirk SDHCI_QUIRK_CLOCK_DIV_ZERO_BROKEN

adds quirk for controllers whose clock divider zero is broken,
sdhci_set_clock function will incorporate this modification.

Signed-off-by: Suneel Garapati <suneel.garapati@xilinx.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>