mmc: cqhci: SDHCI may not work in command queue mode

Check for command queue host as SDHCI controller may work
in non-command queue mode as well, for example, external
storage slot.

Change-Id: Idc1fc3c36f2a8edd8337df5540ce6fce2e078719
Signed-off-by: Neeraj Soni <neersoni@codeaurora.org>