mmc: cqhci: Ensure macro parameters are wrapped in parentheses

Absence of parentheses is not affecting current code, but ensure macro
parameters are wrapped in parentheses.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: a4080225

 ("mmc: cqhci: support for command queue enabled host")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>