mmc: cqhci: add new cqhci_host_ops pre_enable() and post_disable()

Add pre_enable() and post_disable() for cqhci_host_ops.
Add hook functions before cqhci enable and
after cqhci disable for platforms need them.

Signed-off-by: Chun-Hung Wu <chun-hung.wu@mediatek.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/1598520783-25250-2-git-send-email-chun-hung.wu@mediatek.com


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>