sdhci_add_host() allows the Host Controller Capability registers
to be supplied by the calling driver by using
SDHCI_QUIRK_MISSING_CAPS, but the check for the Capabilities bit
SDHCI_CAN_64BIT doesn't use the applied value and instead reads
the Host register directly. This change uses the supplied "caps"
register instead of reading the host register.

This change will allow a calling driver to simply clear the
SDHCI_CAN_64BIT bit in "caps" to handle some cases of
SDHCI_QUIRK2_BROKEN_64_BIT_DMA.
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>