mmc: sdhci: fix SDHCI_QUIRK_NO_HISPD_BIT handling

SD controller with SDHCI_QUIRK_NO_HISPD_BIT quirk probably
use high speed enable bit for other purpose. So this bit
shouldn't be changed for high speed enabling for this type of
SD controller.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>